This chapter encompasses Washington, D.C. and most of Maryland.
In addition to general information on IAEI and our chapter, this page will offer you contact numbers, news of forthcoming meetings and seminars, minutes of previous meetings, and links to other electrical safety web sites.
What follows our logo is the brief general description. If you are in a great hurry though, you have links to various portions of this site, right below here.
One point, though. We are a gathering of colleagues with similar goals. Therefore, I hope that if you find any problem or error on this site you will take a moment to report it. Even better, describe how you believe we can convey the correct information.
Here we go with quick links:
Next meeting or meetings: When, where, and program(s).
George Washington Chapter Phone Numbers and Email Addresses
Useful web sites: Links and descriptions
Biography of the man who revived our chapter in the mid-1980s: Art Hesse
A discussion of CEU-earning activity, including a notice of our forthcoming meeting; and then an index of previous meeting topics, starting with the most recent; then finally minutes, starting with those for our last meeting. Minutes, include detailed reporting of the presentations
Our purpose is to further electrical safety, and in particular to foster electrical education and the uniform application of electrical standards. About a third of us are electrical inspectors, mostly working for local governments, but including quite a few third-party inspectors. The other two-thirds are contractors or their employees, consultants, and representatives of organizations that support IAEI. (The ratio of inspectors to contractors is reversed in our Canadian section; go figure.)
As of Fall 2013, we had sixty-plus local members. We welcome others who might consider joining IAEI. Our meetings are held on the third Tuesday evenings of January, March, May, September, and November. We normally take care of chapter business and then enjoy an educational program.
Continuing Education credits are provided for those current members who attend a full session and sign in properly.
In July, 2008, we were officially added to the list of approved
Continuing Education providers by the Prince George's County Board of
Registration for Master Electricians, Journeyman Electricians,
Apprentice Electricians, Electrical Contractors, and Electrical
Subcontractors. Here's a link for our current
activity. The full version of the minutes of all our meetings to date can be found
below Our meeting minutes are also published in the online version of international magazine, IAEI
Here's a link to an extended obituary of Art Hesse, our chapter's godfather.
Use this link for the web site of IAEI Headquarters
If you have questions or comments about this web page, please call the Chapter secretary at 301-699-8833, 9 a.m. - 9 p.m. If we're out, please use the voicemail. Voicemail is quite reliable except when there's an outage. For other local questions, contact either him or one of the other officers listed below.
Use this link to email the chapter.
George Washington Chapter Phone Numbers and Web Addresses
President: Robert Welborne
Past President: vacant.
Vice President and Membership Director: KarlMirpanah
Secretary-Treasurer: David Shapiro , (301) followed by 699-8833, 9 am - 9 pm; You also can fax, during business hours only, please, to (301) followed by 699-8830 (though faxes are checked somewhat irregularly) His web site is and http://www.davidelishapiro.com/
Links and descriptions
We are a chapter of a Not-for-Profit incorporated association, and have a copy of the Internationl Association's 501(C)(6) form available. Our tax ID number is 522092888.
These are a few web sites that may be useful to people looking for answers to questions on the NEC, IAEI, or our chapter:
http://www.iaei.org -- the International Office -- includes membership information, a bulletin board for Code and other questions, jobs ....
http:/www.gwiaei.org -- links to this very site, with our chapter's news, including meetings, seminars. . .
Various electricians and consultants have sites with useful information, including lots of links to Codes and Standards organizations. They include the following:
<http://www.iaei.org/forums> IAEI's discussion site Our own parent organization's listserv.
<http://www.eng-tips.com>NFPA's codes and enforcement site includes topics including but not limited to electrical.
<http://www.codecheck.com> Redwood Kardon's site includes information on both electrical and other codes.
<http://forums.mikeholt.com>Mike Holt's site
<http://www.electrical-contractor.net> A board that includes discussion of Code violations .
<Http://www.ecmweb.com> is a magazine site that includes pictures of Code violations.
<http://www.necanet.org> includes Code quizzes, discussion of electrical violations.
<http://www.safetylink.com> is largely concerned with international product safety standards, but includes, for example, links to all the Nationally Recognized Testing Laboratories.
A wide range of information is available to help us avoid getting injured or sick as the result of our work. I have summarized reports that I have reason to believe are unbiased but that you don't need to read in full; and I provide links to other reports that don't lend themselves to quick summary.
First, though, an excellent web site. The somewhat-cumbersomely named Electronic Library of Construction Occupational Safety and Health at http://www.elcosh.org/ offers papers on work hazards, product recall notices, and a host of other material categorized by the type of job you're on or by trade.
NIOSH, the National Institute for Occupational Safety and Health, published a report about what it has taken to revive someone who got zapped badly enough that his heart stopped. The answer is CPR within four (4) minutes, and then advanced support from a medic within eight(8). If you leave the victim lying there with their heart stopped much longer than four minutes without at least CPR, they may not survive when you might otherwise have saved them.
NIOSH has looked at this one too. Lockout, tagout, safety grounding, testing: you know the drill.
Sometimes workers make do with deteriorated equipment. NIOSH published a report about people being shocked, even electrocuted, because they plugged a three-prong cord into something so badly damaged that the grounding prong made contact with an energized terminal. Your secretary thinks it's our responsibility to see that sort of bad garbage deenergized and, generally, disposed of.
Here's a 92-page NIOSH manual for electrical students, teaching them about workplace hazards--but only the electrical hazards: http://www.cdc.gov/niosh/docs/2009-113/.
For an overview paper on worker deaths by electrocution, which include statistics by occupation, age, year, voltage level, etc., see this link: http://www.cdc.gov/niosh/docs/98-131/.
There are at least two English-language research and treatment centers focusing on electrical injuries,
the Chicago Center and
reliable links are vetted, they will be added. I probably don't need to tell
you about UL or NFPA as resources.
We have not offered seminars in quite some time. However, online seminars are available
through the International Office, a registered IACET provider. For
information, visit WWW.IAEI.ORG or call 1-800-786-4234. Reports of past meetings are presented below, the
most recent first. Versions can be found in IAEI
News, but since late 2013 only in the online version. Here are the links to our meeting reports, indexed by topic and date: This section starts out with information about our next regular
local meeting, and then we have reports of previous meetings, going
back several years to Y2K.
Our next meeting will take place the third Tuesday of September, September 20, 2016. (If we offer a summer extra, we'll let you know here and, if you're on our list, by email.) We have not yet selected the presenter and program title. Stay tuned.
We will meet by 5:30 PM in Classroom 1-2 of the Prince George's Community College’s Westphalia Training Center at 9109 Westphalia Rd, Upper Marlboro, MD 20774. While the program will begin promptly at 5:30, a number of us collect a little earlier to schmooz, hobnob, hang out.
You’re of course welcome to bring any colleague along, member or non-member. The learning is available to all, even though only members--including people who sign up that evening--gain CEUs.
Also, a normal feature of every chapter meeting is an educational program for which each member who attends the full session earns either one or two CEUs.
We Can't Lose Power (May 2016)
You're Grounded (March 2016)
It's the Law (January 2016)
Kill it!(November 2015)
The code and the Standards(September 2015)
A really up-to-date building (May 2015)
Reading Time-Current Curves for Fuses and Circuit Breakers (March 2015)
Electric Signs. (January 2015)
NFPA Resources, Other codes Needed to Work with the NEC, and More. (November 2014)
Evaluating Water-damaged Electrical Equipment, Evaluating Heat- and Smoke-Damaged Electrical Equipment, AND an introduction to the new article on Low-Voltage Suspended Ceiling Power Distribution Systems. (September 2014)
Selective Coordination and Modern Fuses.(May 2014)
Inspection and Troubleshooting Discussion.(March 2014)
Changes in NEC Contents and Process. (November 2013)
Capacitor Choice and the Effects of Various Possible Faults on Line Design. (September 2013)
Wiring Devices and Circuit Protection. (May 2013)
Common Neutrals. (March 2013)
Lightning protection versus safety bonding; Firehouse Classification; and AIC Calculation. (January 2013)
Grounding-Bonding Feeders to Other Structures; Classifying Firehouse Spaces; and Powering Jockey Pumps. (November 2012)
Generating Plant Visit. (October 2012)
Mistakes Frequently Found on Electrical Plans. (May 2012)
2012 Committed Members' Business Meeting.(March 2012)
2011 NEC Changes Relevant to PV Installations. (January 2012 Part 1)
ACES report (January 2012 Part 2)
Identifying and Dating Violations. (November 2011)
UL's White Book, Listing and Labeling Issues. (September 2011)
Pepco: Procedures and Plans. (May 2011)
New Products and the Code. (March 2011)
Some 2011 Code Changes. (January 2011)
NEMA Services Overview and Stories. (November 2010)
NEMA Lighting Systems Briefing. (September 2010)
NEIS Update. (May 2010--valuable session, but minimal report)
Generators--Installation, Consultation, and Inspection. (March 2010)
2011 ROP Observations. (January 2010)
Assorted Code Topics. (November 2009)
An unusual bit of history. (September 2009)
Meters and electrical measurements. (May 2009)
Grounding and Bonding of Separately Derived Systems.(March 2009)
Fuses and Related Topics.(January 2009)
Code and standards changes over time.(November 2008)
Photovoltaic Installations: Code and Safety Issues. (September 2008)
Primarily, Extensive Deliberation Over Training Plans. (May 2008)
Dimmers and Other Lighting Controls. (March 2008)
Two hours of lively discussion revolving largely around slides of Code violations. (January 2008)
Two hours of information on generator selection and maintenance.(November 2007)
Representatives from UL and NEMA talk about forthcoming NEC Changes.(May 2007)
Thermographic cameras plus some new devices.(March 2007)
Chitchat (January 2007)
Wide-ranging Notes loosely on Section 110.3. (November 2006)
Scattered notes on a miniseminar covering various aspects of grounding.(September 2006)
Code Calculations(May 2006)
Firestopping Systems(January 2006)
Communication Cables, Flamability/Smoke Characteristics, and Codes (November 2005)
Manholes and handholes(May 17, 2005, #1)
Circuit Integrity Cable (May 17, 2005, #2)
Surge Arrestors(November 9, 2004)
Wiremold products and related Code Issues (September 14, 2004)
The Importance of Knowing UL's General Information Directory (January 2004)
The Skinny on Sheaths and Insulation: CMP member Dave Mercier talks about the uses, evaluation, and repair of cables and conductors.(November 2003)
A manufacturers' representative and various members share information about testers and materials.(September 2003)
A LITERAL VERSUS APPLIED NEC; judgment calls on the rules for support of fished cables, and for multiwire circuits.(May 2003)
This is not actually the report of a chapter meeting's program, but of what took place at the American Council for Electrical Safety in April 2003.
2005 NEC changes; a sampling of those proposed, including some accepted by Code panels and some that were rejected, plus information on the process(March 2003)
Testing Laboratory product evaluations (January 2003)
NFPA's other codes, in particular NFPA 5000, their building code (November 2002)
Code enforcement in D.C. and in Annapolis, with special reference to Maryland's "Smart Code" September 2002)
OSHA job site regulations and enforcement activities (May 2002)
AFCIs, a disputation between experts on their effectiveness(March 2002)
Personal Protective Equipment (January 2002)
Electrical codes competing with the NEC(September 2001)
CPSC activities, including research (January 2001)
NEC rules for low-voltage wiring (November 2000)
As additional reliable links are vetted, they will be added. I probably don't need to tell you about UL or NFPA as resources.
We have not offered seminars in quite some time. However, online seminars are available
through the International Office, a registered IACET provider. For
information, visit WWW.IAEI.ORG or call 1-800-786-4234.
Reports of past meetings are presented below, the most recent first. Versions can be found in IAEI News, but since late 2013 only in the online version.
Here are the links to our meeting reports, indexed by topic and date:
This section starts out with information about our next regular local meeting, and then we have reports of previous meetings, going back several years to Y2K.
Our next meeting will take place the third Tuesday of September, September 20, 2016. (If we offer a summer extra, we'll let you know here and, if you're on our list, by email.) We have not yet selected the presenter and program title. Stay tuned.
We will meet by 5:30 PM in Classroom 1-2 of the Prince George's Community College’s Westphalia Training Center at 9109 Westphalia Rd, Upper Marlboro, MD 20774. While the program will begin promptly at 5:30, a number of us collect a little earlier to schmooz, hobnob, hang out.
You’re of course welcome to bring any colleague along, member or non-member. The learning is available to all, even though only members--including people who sign up that evening--gain CEUs.
Our most recent meeting took place Tuesday, May 17, 2016.
The program: have you heard of MS Electrical Training? How about Marty Schumacher, former Chief Electrical Inspector for Harford County, now serving them as a consultant? He gave us a substantial piece of one of his most popular training classes, Emergency Systems and Generator Rules, going over a wider range of rules than most of us knew applied.
We had a good little group, including members driving from as far away as Kent Island, MD and Tysons Corners, Virginia. All in all, not counting our speaker we had three inspector members, eleven associate members, and, among them, at least four P.E.s. The five members in the next picture include two fitting each category!
Looking at Article 445, Marty talked about Hurricane Sandy, and how generators and their fuel sources got flooded out because they were within the 100-year floodplain. The Federal Emergency Management Administration (FEMA) recommends keeping a fuel supply on hand sufficient for three days. Why? Even generator operators who had contracts guaranteeing constant supply got nothing for up to three days because the suppliers' trucks couldn't move.The NEC requires a two-hour fuel supply, so that buildings can be evacuated over 90 minutes, with the extra 30 minute' worth to account for unreliable fuel or measures. Hospitals covered by NFPA 99 need far greater fuel supplies.
One mistake that people, including Code officials, often make about generator power is that they treat lines from generators as service conductors, while they actually are characterized as feeders.
States adopt building codes, such as NFPA 54, one of the codes addressing generators. However, some of the documents that apply are standards rather than codes. NFPA 110 is an example; that is where you find the requirements for rooms enclosing indoor generators.
The electrical contractor sometimes is the sole person in charge of the generator installation, and the electrical inspector likewise. The fire marshal does come by, but this can be a good while after the system is put into operation. If he finds violations, though, part of the installation might need to be redone. Marty told the story of a Columbia installation that needed its generator moved two feet further away from the side of a supermarket where it had been operating for a good year. It was not equipment they could do without, either, so they had work going day and night to bring it into compliance. Those who were at the meeting knew the supermarket that got nailed. Its designers apparently overlooked the requirement, and so did the original inspector.
Marty seemed dismissive, at first, in talking about NEC Section 445.13, regarding wire sizing. It's not that he discounts any part of the Code; he doesn't, although he talks about some pieces as more urgent to enforce in detail than others.
However, Marty note that 445.13 can be misapplied. It addresses the size of wire from a generator to the first overcurrent device; and most commonly that overcurrent device is located on the generator enclosure itself. Therefore, 445.13 sizing is handled by the manufacturer, at the factory. Not always, though. But when the overcurrent device is provided on the transformer enclosure, AHJs don't have the NEC authority to require that the downstream conductors be sized at 115% of the generator's rating.
NEC Section 445.18 concerns the readily accessible shutoff. Marty spent quite a lot of time on the concept of "readily accessible": not even requiring the use of standard tools; of limiting access to non-authorized persons: a guard-protected location can provide this without limiting ready access to qualified persons; and of providing permanent locking means. Dan Verma, one of the two intent engineers below, behind Karl, had asked about accessibility to vandals. Marty responded that if it is an emergency system generator's switch, it must not be accessible to unqualified people, in the NEC's wording, or "unauthorized" people in the International Building Code's language. Later he emphasized that a generator or shutoff that serves any emergency loads is considered emergency equipment, and must be rated and treated as such.
Marty also commented that usually a readily-accessible gas shutoff will serve this functional purpose. David asked whether anyone knew how long a generator was likely to pump out power, once the gas shutoff was, err, shut off. No one knew. Marty guessed maybe five seconds; Dan guessed ten. When he was dealing with disconnects "within sight," he pointed out that a visible, lockable, specially-built outdoor room (shack?) marked to indicate that it contains the disconnect will have some AHJs accepting and some rejecting it as representing a "disconnect within sight."
From the very start, Marty was very welcoming. When people were slow to arrive due to miserable traffic and weather, he expressed himself willing to start any time it was good for us. He remembered people's names, and addressed us individually. He complimented people on their questions. He even gave away LED pens to some of the people who raised points.
Harry Langway, the member who probably drove the longest distance--but that isn't what earned him his pen/light--is seen here in the far corner of the group he came with.
While the rules for services and disconnects are not necessarily that different--like thre rules for the three types of backup power--you have to read the right section. For generator power--feeders--entering or passing through a building, the disconnect is required by Section 225.3, Disconnecing Means, and its location specified by Section 225.32. Marty spent a little time on the concept of "nearest the point of entrance." Marty Schumacher's explanation grabs everyone in sight except Joey, who's deep in thought.While a couple of our P.E./inspectors suggested that specifying a distance woud make sense, Marty roundly overcame that concept. Every Code session someone proposes this, but there are too many variables. If you're running 100 amp feeders they are a lot more flexible than feeders carrying five times that much current. If it makes sense to come into a house at ceiling level to keep your conductors out of permanent moisture, it makes sense to allow a few extra feet before the disconnect, in order to have the disconnect readily acessible without having to build a platform in front of it.
Marty asked us to guess the top one of the top 20 violations identified by him and the inspectors and electricians he's asked. The 20 most common or the 20 most serious? Both, he said.
His answer: 110.3, and basically 110.3(B) because in his view inspectors have no good basis other than listing instructions to use in accepting products and installations. Another issue he feels strongly about is the need to block moisture from coming up as raceways enter an enclosure from below ground level.
Harry asked whether he would accept duct sealant for the purpose. Here agian, Marty saw it too ways. Duxseal is better than what 90-plus percent of electricians do, whch is nothing. On the other hand, he can't fault inspectors for turning down its use, because it is not listed for the purpose. What is particualrly different about our cabinets compared to 30 or 35 years ago, he asked. Dan Verma got this one, and earned himself a pen/light: electronics. Marty asked this to make his point about how vulnerable equipment is nowadays to moisture. Pete had a thought about this:
He had fun talking about how the Washington, D.C. area Metro system has not just problems with moisture in their raceways but actual water moving in them.
From here Marty went briefly to the National Fuel Gas Code, mentioning the need to bond gas piping, even to specially bond it on the customer side when yellow CSST has been installed. Moving on, he stopped in at Section 210.12(B). When you install a generator and a transfer switch, is this considered new wiring? Do the circuits it serves now have to get AFCI protection? No. So long as no greater than a six foot extension is involved in the repair or replacement of the existing service and circuitry, and so long as no receptacle is added, AFCI protection does not need to be installed.
Now Marty moved to non-coincidental loads, which I will not review here. The next topic was a particularly nasty one: other rules. There are a whole bunch of other codes that apply to generators. NFPA 37 talks about engine locations. It says that they have to be at least five feet from building openings, and at least five feet from combustible walls. There's an exception to the latter if the engine housing is capable of containing fire for an hour and not ignite combustible materials outside it.
Marty brought up a difficult example of tis application. Generac claimed that it had demonstrated its equipment's ability to comply with the exception, so long as an installer complied with its instructions. Baltimore County, though, wanted proof. They wanted Generac to demostrate to them that it complied.
Besides NFPA 37, there are the rules for fuel storage, NFPA 58 for outdoor propane tanks, NFPA 30 for outdoor diesel tanks, and NFPA 110 for gas. These specify minimum distances from the property line and from the building, which in some cases depend on how much fuel is stored. NFPA 110 specifies that the shutoff for gas serving an emergency power generator--not a solely-optional power generator--must be to the line side of the main gas shutoff. There must be a permanent label at each shutoff, and they should identify the location of the other shutoff if it is remote.
Marty Walsh, City of Alexandria inspector and the first person to arrive this afternoon, said he needed to revisit a recent inspection, based on what he learned tonight. It's about safety.
Next our presenter opened a discussion of exit signs. NFPA1 Section 188.8.131.52 says the signs must be contrasting color for visibility. They could be red, they could be green, and it strikes him as silly to specify that they must be one particular color within a jurisdiction. Yes, designeers normally keep them one particular color in one building, but depending on how it is decorated red might be a better contrast or green might.
How about location? in California, maybe in some other jurisdictions, and in Europe, they are mounted close to the floor so that they will stay unobscured by the smoke a little longer. Marty and Pete both consider this highly unimportant: Marty because the whole room fills so very quickly, and its occupants die, and Pete also because mounting them nearer the floor increases the chance that they will be blocked. Marty suggested googling the Annapolis Christmas Tree Fire, in which a room filled from ceiling to floor in 21 seconds.
Now Marty hammered on the importance of a new rule in Section 700.8, requiring that emegency systems be given surge protection. These MOVs will burn out, occasionally, but in doing so they are protecting equipment so as to extend its life sometimes 100% by absorbing the small surges that wear it prematurely.
Now we get to a tricky bit of definition. Section 700.5(D) says that if there are any emergency loads on the panel fed by a generator, an emergency-rated transfer switch must be installed. Expensively. And an emergency transfer switch can only feed an emergency-rated panel, also expensive. This does not, however, mean that all the loads fed from that panel must be emergency loads.
Section 700.7(A) says that the panelboards must have placards bearing signs that tell were all the generators are located. The emergency panels and generators and transfer switches must be labeled as such, without the use of codes, so it is immediately apparent what they do. All enclosures serving the emergency circuits, even junction boxes, must be clearly labeled as such. Red coloring is not enough.
There is also a rule requiring a placard by the meter serving the emergency loads, but this usually is less critical because often the generator is right there.
As we approached the end of the evening, Marty touched on emergency lighting. If there are emergency lights served by battery packs, the breakers serving them must be so identified at their panelboards. This is a case where Marty sees a real advantage to locking the breaker, panel, or room so that these circuits are less likely to be unthinkingly turned off.
Harry picked up a problem with an image Marty showed, of a switchgear room with regular doorknobs. Marty saluted him for his observation. In the 2011 NEC panic hardware was required for rooms with over 1200 amps controlled; in the 2014 it moved down to 800 amps. "Panic hardware," Marty commented, was a solution with the previous wording, which involved operation by simple pressure. The problem with this, he said, is that lever locks operate by simple pressure. Better than knobs, yes, but not as good as panic bars that move in the direction of the door's opening.
Two last items: First he discussed the problems with selective coordination. While our Bussman representative's presentation on selective coordination indicated that circuit breakers' tripping curves could be coordinated just as fuses can, Marty has been told that to get .01 second tripping at the branch circuit level in order to selectrively coordinate the protection of emergency systems, you need fuses. And why should you need this, they complain, when hospitals only require tripping within 0.1 second at the branch circuit level. He tells the engineers to do the best they can.
The second issue he brought up concerns plug-in, portable home generators. When these are connected to backfeed home wiring systems via 4-wre twistlock inlets, as is common in rural areas that suffer extended outages, you have a violation. The violation is caused by the fact that the portable generators have their grounds and neutral bonded, making them "separately derived systems." Marty discussed this earlier, and repeatedly: generators need to be labeled to indicate whether their grounds are bonded to the XO point. When you tie power from separately-derived system into a home wiring system that normally is fed by a utility, without an isolating transfer switch, you have created multi-point grounding. He is not aware of hazards caused by the use of these generators leading to stray voltages, but he has not investigated it and he does know it is illegal, however common.
With this, we shut down for the evening, with a grateful round of applause and an exchange of business cards.
Our next-most-recent meeting took place Tuesday, March 15, 2016.
Wayne Robinson, the former Chief Electrical Inspector of Prince George's County and former IAEI chapter president, the inventor of the Kenny Clamp, the well-known consultant and paid instructor, came to present a 2 ½ hour program on grounding. That’s right: two-and-a-half hours of Continuing Education credit for attending this meeting, for IAEI members. As always, people were welcome to bring any colleagues along, members or non-members. The learning at our regular meetings is available to all. This time, five non-members and two lapsed members joined us, and two joined IAEI at the meeting. Counting them, and Wayne, we had 18: 3 inspector members, 5 nonmembers, and 10 associate members.
We planned to start promptly and take very short breaks if any, to earn 2 1/2 hours of Continuing Education credit and still get out not too long after 8 PM. Due to system compatability issues, it took a while to fully connect Wayne's laptop to the projection system, so it was almost 5:40 when we started. However, we chose to run till 8:30, and only took one break, so we earned a full three hours of CE credit. we completed an item of chapter business after the presentation.
We also learned a good bit. Even if it was our tradition to recount everything here, it wouldn't be possible. In addition to note-taking, the Secretary needs to snap pictures and handle administrivia. Still, I can share some samples and highlights.(Even other attendees occasionally took a break from intently focusing on the speaker. .
Inspectors with their own rules:
"What should I do when a jurisdictional inspector demands that I do something the adopted code does not require?" More than one attendee wanted to know this, though the particular issue that had been raised concerned an inspector in the Baltimore area. Wayne had a number of answers. In most cases, if the requirement is small, you do what he says, so as to get the job finaled. However, you also can write a letter to the inspector's boss for clarification of the inspector's interpretation. In PG County and many other counties in Maryland, the Electrical Board was the ultimate authority, so you can write to them. If you can document that a field inspector has unnecessarily caused homeowners to pay for non-required work, this will get the situation corrected. Field inspectors need to provide written correction orders to verify the code compliance of their instructions. Most counties require that instructions for corrections be in writing. Verbal communications are slippier than written.
Resources for information on grounding issues.
Wayne recommends two books on grounding: Soares Book on Grounding and Bonding, published by the IAEI; and Applied Grounding and Bonding, by Michael Johnston.
Bare versus insulated grounding conductors in raceways.
Wayne made a strong point that there is an advantage to pulling a green-insulated grounding conductor, rather than a bare one. Research apparently shows that during ground-faults, the grounding conductor's i2r heating is sufficient to damage the insulation on nearby circuit conductors. If the grounding conductor is insulated, though, heat transfer is slowed sufficiently that the heat dissipates gradually enough that it doesn't harm the current-carrying conductors. Research he's seen indicates that under fault conditions approximately equal amounts of ground-fault current are carried by all properly installed metallic grounding paths; on the outside of a metallic raceway, when the raceway contains a properly-installed, suitably-sized grounding conductor, and by the grounding conductor.
250.4(A)(5) Effective ground-fault current path
Wayne spent a few minutes talking about the perils of leaving out pieces or actions that are needed to ensure that the grounding path is low-impedance, and about the importance of taking care of them. Right now, not putting it off or leaving it to someone else. This includes getting the right screw and installing it when a setscrew coupling has lost one of its screws; and tightening locknuts. Put it off and overlook doing it, and what are you likely to get when there's a ground fault? Arcs, and damaged equipment.
Wayne took a moment to ask us how much current the neutral-bonding screw in a residential panelboard is required to be able to carry. According to UL 67, it's 30 amps, just 30. He brought this up in talking about NEC Section 200.2(B). A grounding conductor is not expected to carry significant current regularly, but a grounded conductor is. That's one reason why the grounded conductors' return paths should not rely on the cabinet metal plus the bonding screw to get back to the incoming neutral. Yet Wayne frequently sees white conductors attached to a grounding bar htat's simply attached to the cabinet--both in service panels and in subpanels. And it's a violation in either type.
Ground Detectors and ground faults in ungrounded systems.
Wayne talked next about three-phase systems that are designed without a normal, low-impedance ground. These all require ground detectors, ground alarms, some means of alerting the operators to terminate the process being fed and identify the source of the problem, before a second ground creates a phase-to-phase short.
With high-impedance-grounded systems, it's easier to track down the fault than with ungrounded systems.
Now Wayne moved to Section 250.24(A)(1), choosing the point of attachment of the grounding electrode conductor (GEC).
A colleague of Wayne's in Georgia reported a local requirement that the connection point must be at the weatherhead. Why? No one was going to bring a ladder just in order to disconnect it. (Perhaps in that area there are more pranksters than ignorant siding installers.)
What's the purpose of the grounding electrode? Wayne wanted to make sure everyone recognized that it is the dissipation of lightning energy. How about the 25-ohm maximum? He didn't have a source for that number, but Harry Langway reported that a magazine he reads said that the electrical code got that number from the telegraphers. Where that group got it, he didn't know. Cellular towers, he commented, use tinned or silvered GECs, perhaps because they try to keep their grounds at less than three (3) ohms to the earth.
Diving down a rabbit hole, Wayne mentioned that he advises against running cables carrying 13.8 kV in cable trays. Even in power houses, it is run concrete-encased, and the walls are marked to indicate just where it is run. One consultee asked him why not run it in trays, as had been specced. He explained that if it arced, the arc would reach down from the overhead cable tray and kill her. She took his advice and changed her plan to run it in trays.
Now Wayne moved on to Section 250.24(A)(5), Load-side grounding.
In his model, if you install grounded conductors with grounding conductors downstream of the service panel, part of a short circuit will return on the neutral wire and part will circulate in the subpanel. (I don't understand this statement-David.) This will reduce the amount of current flowing back through the breaker so that it won't trip when it should.
Wayne asked how many in the room have surge protectors in their houses. Few of us raised our hands. He pointed out that many voltage spikes and surges due to nearby lightning strikes can damage electronic equipment--he referenced his wife's treadmill--and that Surge Protective Devices (SVPs) will provide protection. Incidentally, this term now covers both service and downstream protectors, as the term, "Transient Voltage Surge Suppression" is no longer used.
Wayne now touched on the legal options for bonding service panels and wireways between meters and service panels. You can bring grounding electrode conductors to the trough and be done, or you can bring them to each of the service panels. One is less expensive, both are legal.
Transfer switches associated with 3-phase generators now need to be marked to indicate whether they transfer three poles or four. A 3-pole transfer switch, with its xo terminal bonded to the case, has the potential of sending unbalanced current through the neutral connection up to the utility transformer. Because transformers work in either direction, this means high voltage being sent up the line from the utility primary, posing a serious hazard to the utility workers. Using a three-pole transfer switch, creating a separately-derived system, rather than a 4-pole transfer switch, requires a special permit in this area. It is issued by the Public Service Commission, and there is a 6-8 month delay between application and issuance.
Back to GECs.
Just as the 3-pole transfer switches serving unbalanced loads impose voltage on the neutral all the way back to the utility worker, so unbalanced loads coming directly or indirectly out of a service panel in any grounded system impose voltage on the GEC. This makes it important that you shut down the main before disturbing GEC connections.
250.30(A)(2), 250.102(C) and Table 250.102(C)(1), 250.148(C)
For bonding generators, people used to run 1/4-20 screws through ventilation slots to hold ground bars, maybe with fender washers. This no longer is legal; the bars have to be supported from the side of the generator.
250.64(D)(1) When running a common GEC to multiple service enclosures, the GEC must be sized larger than if the GEC is run to a bonding point upstream, between the meter and the service panels. Still, both choices are legal.
Wayne fulminated a bit over the arbitrary definition of "Irreversible," forbidding the use of split-bolt connectors along a GEC but permitting the use of terminations with any listed connector to a sufficiently-long, accessible plate at least 1/4 in thick by 2 in wide.
Wayne commented, with the help of an illustration, that whether or not there is a switch associated with a generator to disconnect power from it to inside a building it serves determines whether its ground is a GEC or merely a grounding conductor.
Around now Wayne commented on Ufer-related GEC mischief. He's seen cases where a builder poured a slab containing a concrete-encased electrode, leaving maybe 10 ft of 4-gage copper GEC coiled outside the slab. Some crook would come along and steal the copper, and when the builder discovered this he'd drill a hole in the slab, stick the end of a new "GEC" in the hole with some builder's cement, fill the hole, and present this as the Ufer. Now we're explicitly authorized to bond the GEC to rebar that was turned up, above the slab, beyond the end of 20 ft. of concrete-encased rebar--the Ufer grounding electrode. Who's going to steal a foot of rebar?
Supporting the GEC.
There are a few rules that often are overlooked regarding how a GEC exits a panel and travels to its electrode or electrodes. First, there is a requirement for strain relief in UL 467. Wayne commented that this does not mean bringing it out of the panel through an NM connector: those connectors are not listed for the purpose (any more than a yellow or red wirenut is listed for splicing grounding conductors). Second, it can't leave the panel through a designated weep hole. Third, Section 250.8 says it must be adequately supported. Finally, if you run it through a metallic raceway, you have to bond the raceway with a bonding jumper the same size as the GEC. Incidentally, there's the question of how to size GECs. If you don't read the rules carefully, and size it way larger than necessary, you could waste the customer's money. If you oversize the GEC, you're investing in all that extra copper all the way back to, say, the water entrance. Back in 1975, Wayne told us, you could bond to any handy water pipe (under Section 250.50 (a) and (b) Exception for extensions of ungrounded branch circuits).
Two more asides.
Wayne commented briefly on AFCIs. The idea is a good one, he said, and it's far from new. However, as a new technology, the AFCI remains too vulnerable. High-frequency devices can trip it. Imagine installing an AFCI near a ham radio operator.
Finally, where do we get the idea that two ground rods are good enough to do the trick, and if you drive them you don't need additional electrodes? It comes from the rule for temporary services. Without building steel, without water pipes, wthout concrete-encased electrodes, you drove two electrodes, at least six feet apart. If it was good enough for temporary services, somebody figured, it's good enough for permanent installations.
Because one inspector member who had not voted online, Mike Thomas, was there and made himself available, we gained the quorum needed to finish voting. Therefore, our annual election was completed. There were no new nominations and nobody volunteered either to fill an unfilled office or to challenge an incumbent. Therefore, we retained Robert Welborne as President, Karl Mirpanah as Vice President, and David Shapiro as Secretary-treasurer and Section Representative.
We had four speakers on January 19, each of whom allowed time for questions.
David Shapiro, State of Maryland authorized electrical inspector and long-term electrical writer, briefly introduced the issues of Code adoption and amendment:
What does Section 90.4 mean, talking about enforcement?
We looked at an original 1925 Code book, in which essentially the same rule was found as Sec 205a. Welmoed Sisson, a first-time visitor to our meeting, read it for us: "This Code shall be understood to treat only of approved materials, devices . . .and methods"
Next, in the modern Section 90.4, we read that it is intended to be mandatory for use by government bodies AND insurance inspectors. Specifically, they are authorized to perform three functions:
They give Special Permission
Special Permission requires an approach that provides equivalent safety.
When new rules require unavailable products&c, AHJs MAY accept compliance with previous rules OR they may only accept different alternatives, depending on the reason the requirements were changed.
Why is this for enforcement by insurance inspectors? We looked at what several old Code books tell us about who created the Code, and who was listed as publisher:
Underwriters, meaning the insurance industry, were behind it all along; right until the early 1950s.
If you look for a section on Special Permission, David noted, Section 90.2 (C) is where we find the term highlighted. However, 90.2(C) is only about connection to service conductors, despite the bold print. Section 90.4 is where you find the more-common type of special permission.
Next, we looked at what from
2008-forward has been Annex H: Administration & Enforcement.
What do What does Annex H offer? It provides a convenient, ready-made framework for a jurisdiction to use when newly taking on NEC enforcement. At least one area jurisdiction explicitly incorporates a piece of Annex H into the electrical code as they enforce it.
David also reviewed what is being enforced by other jurisdictions in the general area besides the three that the following speakers discussed. Inspector Member Bob Sisson, with 13 years of experience as a Home Inspector, talked about some of the fine detail. A number of counties include cities and even parts of cities that do their own inspection, have their own local amendments, and perform their own interpretations of the NEC. Most of Montgomery County, fortunately, has a record of permits and inspections available online. This can be awfully handy to someone who is investigating the condition of a building being considered for purchase: old, unclosed permits? Evident work with no permits evident? Serious warning signs, especially given that the American Society of Home Inspectors Scope of Practice does not include pulling the cover plates off wiring devices.
David distributed handouts containing the links to local jurisdictions' Code adoption and amendment sites, and as a lagniappe, a copy of all of Howard County, MD's electrical amendments. He also offered disks containing somewhat dated versions of the UL White Book; these were eagerly accepted. He did remind attendees that the latest version of the White Book is available for downloading. www.ul.com/whitebook.
After this we took a few minutes' break.
As you can see, nobody's attention wandered from speakers and Code.
Robert Welborne, PE, Chief Electrical Inspector and Electrical Plan Reviewer, Prince George's County, MD (PG) talked about finally bringing his county up to date, with the adoption and enforcement of the 2014 NEC.
He handed out copies of the adopting legislation, including amendments.
Until recently, Prince George's County unhappily lagged behind other jurisdictions. Now they have a chief once again--after too long a gap--and as of January 11 they have been right up to date. Robert has been working hard to bring his department to the point that they can consistently enforce the Code as written.
Like many other jurisdictions, PG is trying to move to an all-electronic permit and scheduling system. Once they have shifted to fully electronic permitting, they plan to have a couple of computers available for public use in their office. This way, contractors such as our loyal member Johnny Hoff (whose extremely rare absence was due to a head cold), who don't have computers, will be able to come in and pull permits. This is the theory. For now, though, they have not provided those public-use computers or work stations, so you still can walk in and pull a permit.
Bob Sisson asked Robert whether a booster, or jockey, pump for a fire-protection sprinkler system is required to have a backup. Robert said, "Yes, but not in a residence." A little further discusion led to the consensus that it is a good idea to have something such as bedroom or bathroom lights die--something that's hard to overlook--when sprinklers or smoke alarms lose power. So there's a definite advantage to not giving them dedicated circuits.
Back to the topic of online permits: every Wednesday, the County gives a class on how to use the PG system. Each Master Electrician attending gets a unique password.
Steve Thomas of Mongomery County interjected that their permit system is now 50-60% online.
Someone commented that with no signature, just a computerized password, someone else can easily apply for a permit in your name. Robert responded that people sell permits all the time.
Robert asked us how many have installed solar systems, and how many have inspected them. There were no answers. Robert said that he has been inspecting the installations, and failing 70-80% of the 200-some he's investigated. They are mostly performed by solar energy companies.
Home purchasers, he warned, don't pay attention to the fact that the solar panels are rarely the property of the homeowners. Most commonly they are subject to long-term leases from the installing companies. This being the case, the purchasers have to qualify to take over the leases. If they don't, their newly purchased homes are subject to lien.
Robert also asked whether people have seen inverters connected ahead of services, with no overcurrent devices on the MLO panels. Rick Panizari checked him out: are you talking about those old buildings in Hyattsville, with six circuits?
That's what he meant.
The next topic was inspectors' side obervations. Some inspectors, especially third-party inspectors, have understood their job to be evaluating the work covered under the permit they were brought in to pass or fail, and nothing but that.
That's not how he wants it enforced. Minor stuff? Sure, leave that be. But not long ago he laid down the law regarding a significant side observation: aluminum SE cable whose jacket was frayed to the point that the bare neutral lay against a house's aluminum siding. Robert requires inspectors who are there to look at other items to call out safety problems on the order of this one.
Getting back to solar installations, briefly, there is the clearance requirement to enable firefighters to get on roofs to ventilate. Solar installation companies have asked for waiver of the three-foot-clearance rule on the ground that firefighters no longer do this.
The proposal is still being considered
Robert's final issue is with Professional Engineers, PEs. Licensed engineers are still cross-stamping, a practice that now is forbidden. And Robert is not the only one to come across this, where engineers take responsibility to--theoretically--supervise work in an area where they have no documented training.
Steve Thomas of Montgomery County commented that when there is no tap ahead of the main, and no circuit breaker larger than 40 amps, they don't require a full plan review of a solar installation.
Karl Mirpanah, MBA, long-time DCRA-authorized Third-Party Inspector in Washington, D.C., distributed a handsome folder showing D.C.'s local amendments and materials associated with D.C.'s Third-Party enforcement of the Code and amendments, and talked about these subjects. Its contents included descriptions of the International Building Code (IBC) Occupancy Classifications. He and Robert discussed firehouse classifications.
Bob Sisson described a so-called home catering business: it used several types of commercial equipment. How then could it qualify as strictly residential?
Welmoed Sisson looked at the Fire Alarm Notes on Karl's Page 23, and asked whether it applies to residential or commertial occupancies. Karl said "Both."
Karl said there is now an online application for third party inspection. Each Third Party Inspector has a unique password; it shouldn't take months to get an inspection performed and a permit finaled. This is Project Dox.
Karl was asked, "Does this help?"
We proceeded without a break. Montgomery County was represented by Steve Thomas--a master electrician himself--who has been inspecting for 29 years. He had been in charge of residential wiring inspection for at least six years and now is in charge of every kind of inspection of commercial construction.
Commercial work certainly is not his only area of expertise, nor the only topic he, or any other presenter, addressed--either in their presentations or in answering questions.
Steve shared both the Code requirements that are enforced right now, AND a draft version of the amendments they are proposing for inclusion with the soon-to-be-adopted (they hope and expect) 2014 NEC.
Steve started by saying he was not about go through his county's rules item by item. However, he addressed some highlights, before there were just so many questions that metaphorically he was carried out still answering them.
Steve began with a discussion of the clearance required of solar installations on roofs in his county. It's three feet for residences and four feet for commercial installations, except where a commercial building's roof looks like that of a residence, in which case the three-foot rule applies.
Another rule (amendment) concerns aluminum wiring. It is only accepted in sizes 2 AWG and larger, and only for use in services and feeders.
On to Ufer grounds. These are required as the minimum grounding system in a new building. If there is sufficient building steel or underground copper water line to serve as an electrode, it needs to be tied in to the Ufer.
Bob Sisson commented that it has been quite a while since he last saw copper underground water lines run.As a sideline, we heard now about the class action lawsuit against the Zurn corporation for leaking fittings used on PEX (cross-linked polyethylene) tubing, a common alternative to copper plumbing. Unsurprisingly, we also talked about CSST gas tubing.
Another comment from Bob concerned the need to bond metal gas line and its fittings. The International Fuel Gas Code (IFGC) specifies a minimum bonding conductor size of 6 AWG. However, unlike NFPA 54, the IFGC rule may only apply to commercial installations.
Bob also mentioned seeing bonding clamps on plastic, on a number of inspections. Sigh.
A number of members commented on protective equipment or disconnects that were made inaccessible by being mounted, for example, on walls in front of which the equipment they controlled was installed. Steve commented on accessibility of, for example, GFCIs, that where you had to open a door to get at the GFCI, simply by pulling a handle, he considered this perfectly accessible.
Karl now asked Steve whether Montgomery County accepts the use of isolated, battery-operated smoke alarms.
Steve said he is willing to allow them, even without wireless interconnection, in the case of alteration or addition. This may not offer as much protection as an interconnected system, but it is less expensive, and with one in each bedroom and one outside the bedrooms there's at least some protection.
Robert commented that in PG he does require interconnection.
Steve said he's gotten cursed up and down for requiring better protection. In one house, the alarms went off and no one woke--not the parents, not the children--just the nanny. The sprinklers saved their lives. What sprinklers? Where 50% or more of the house is modified, Montgomery requires sprinklers.
Monica Cortez commented that R38 or R49 insulation is required over sprinkler piping in order to protect it from freezing.
Welmoed asked, "If there is unprofessional work, what can a homebuyer do?"
Steve talked about when even a professional has to pull a permit. Replacing a device, no. Even replacing a device with an Al/Cu or Co/Alr rated device on aluminum wiring, no. However, even installing one transition device to join copper and aluminum wiring does require a permit and inspection.
How about postcard permits? Montgomery County used to issue these, each one good for installations of up to ten devices. The installations were self-certified by the master electrician. No more, Steve said. They found that installers would send these in, in place of pulling a regular permit and getting inspected, when they installed far more than ten devices.
They have a rule in Montgomery County limiting the number of devices on one branch circuit, even residential, to ten. Well, this is being modified: ten receptacles is a reasonable number. however, now that luminaires are becoming so much more efficient, the restriction is being eased.
One last item: the Leisure World continuous care retirement community is in Montgomery County. The facility has some aluminum wiring--and Federal Pacific panels protecting it! The State Fire Marshal has given them six months to abate the danger.
With this, we closed the meeting, in order to avoid outstaying our welcome. If not for the time--8:15 or 8:20--we would have been happy to keep going.
Members who attended earned two hours of Continuing Education credits. IAEI's International Office has authorized IACET-recognized C.E. credits and will duly issue certificates. These will be distributed at our March 15 meeting.
Rather than interrupt the program to hold a business meeting, we will handle that by email.
Those who attended received handouts containing links to can use to look up local amendments and track rule changes. As mentioned earlier, they also received printouts of some jurisdictions' Code amendments. The latter, those who missed the meeting don't get.
What electrical code is enforced in Maryland?
Anne Arundel, Howard, Frederick, Carroll, and Charles Counties all have adopted the 2014 NEC. Mostly they’re also on the 2015 Fire Code, Life Safety Code, IBC, and IRC; and at least the 2012 Energy Code. Some of these may affect wiring.
What are the local amendments?
On to Washington, D.C.: DC is on the 2011 NEC, with minimal local amendment. You’ll find that here: http://dcregs.dc.gov/Gateway/TitleHome.aspx?TitleNumber=12-C
Lastly, Northern Virginia. Local jurisdictions in Virginia all use the 2011 NEC, all with the same amendments, the Virginia Uniform Construction Code amendments. Read them at: http://codes.iccsafe.org/app/book/content/VA/2012_VA_Construction_HTML/Chapter%2027.html
Want hard copy of the amendments? I believe you have to buy it from the International Code Council.Kill it! When is a panel so bad that you have to shut off power?
This is the report of the George Washington Chapter’s November 17, 2015 meeting. We had ten attendees: one nonmember guest, six associate members, and three inspector members. The latter include Robert Young, who’s in the process of joining.
Most of us gathered a bit before the official time of 5:30 and socialized. Once we settled down, Secretary-treasurer David Shapiro began with a couple of items from the 2015 Eastern Section meeting. First he described a reported variation in how Nationally Recognized Testing Laboratories choose standards to use when they evaluate products for listing. Next he spoke of the honor earned by former chapter member Harry Langway. Having moved into the territory of the DelMarva division of the Baltimore Chapter, Harry found that no meetings were held locally. He volunteered to do whatever it would take to revive the chapter. In consequence, the Eastern Section Board agreed with the Baltimore Chapter’s proposal to elevate him to Senior Associate Member so that he can take on the role of President. Harry was at our meeting, but had not yet heard any of this himself.
David also posted our balance sheet on the screen. Nobody responded with questions or comments.
Next--still before 6:00 PM--Chapter President and Prince George’s County Chief Electrical Inspector Robert Welborne reviewed Section 605.9(D), the last item in the Article on Office Furnishings. He wanted to make clear the fact that installers can serve office furnishings using a multiwire circuit, as we normally understand the term–inside the wall. We just can’t run multiple energized conductors with a single neutral into a office furnishing of the types covered in 605.9.
Richard Panizari spoke up a little later, noting that he’s never seen field-wired, plug-connected office furnishings. This means they’ve come from the factory with the cord and plug, listed this way by the testing laboratory. So no worries.
Robert also told us about some changes in the Prince Georges County, Maryland electrical permit process:
* Not too long from now, all our permit applications will have to be submitted electronically. The plan is to require this of all electrical permits by February 1, 2016; of all mechanical permits by March 1.
* The final, official adoption of the 2014 NEC has passed the legislature, and will be enforced as of the beginning of 2016.
Subsequent to the meeting, but of interest to many who read this report, Robert added a last announcement. There have been a surprising number of forged Master-Electrician signatures on permits. Therefore, for so long as bringing in a paper permit application continues to be accepted, if anyone but the Master Electrician brings it in, the application must be accompanies with the Master’s dated authorization, on letterhead, naming the agent being authorized.
When Robert was done, instead of taking a break we kept going.
David continued the program with a discussion short-titled, “Kill it!” He began with a discussion of the variety of electrical hazards. After a general overview, he started with images of an ongoing, apparent, electrically-induced fire risk in a public setting–the Home Depot store in College Park, MD. He commented that big box stores are not included in the examples we’re given of Assembly Occupancies, but they do seem to collect large enough numbers of people to qualify. Therefore it seems important to eliminate electrical violations that could at the least cause sprinklers to operate and customers to chase each other out.
He followed this with an image of a passive electrical safety risk: a home CPAP (Continuous Positive Airway Pressurization) machine in use to maintain breathing during sleep. This emphasized that a home is a very different setting, but also one characterized by potentially high risk even if only a handful of people are present. Finally, he showed three slides of a burned Stablok panel as an example of electrical safety equipment that had created not only passive but even active hazard. (These slides were provided by courtesy of David Neuman, Dave’s Electrical Service Ltd., Ohio.)
This served as a way to lead into the main issue of the evening: when is a panel in such bad shape it should not continue in service? Another chapter member, home inspector JD Grewell, had recommended to a homeowner that she contact David, to add the muscle of an electrician to the recommendation he had provided. David was able to do just that, with the help of Montgomery County personnel. He visited the high-rise condominium and on getting back called the county. He talked with Mark Nauman and Steve Thomas, and enclosed a couple of pictures from the panel to emphasize the seriousness of the deterioration. Inspector Tommy Flippo was sent out that afternoon–he would have come out immediately, but the customer couldn’t get back to the condo right away!
As soon as Mr. Flippo gained access to the electric room, he shut off power to the unit. This was in late-September. It remained off as of the time of our meeting and beyond. The process of getting the leak diagnosed and corrected was extremely drawn-out.
After preparing his reports, David suggested that the homeowner contact Joe Panizari for the electrical portion of the needed repairs. Happily, Joe was present at this evening’s chapter meeting and contributed additional information.
The electrical disconnects for the condo are located in a locked basement electrical room, with a distribution panel in each apartment unit. David’s opening slide showed drywall damage below the penthouse’s panelboard. The condominium’s management corporation had hired a consulting engineer. David shared the engineer’s report, in two slides, with information that would identify the engineer removed.
The engineer had come by with an electrician and concluded that the leak was due to water descending through one raceway. It entered that raceway, he determined, because it fed into the bottom of an indoor-rated trough subject to rain. He recommended caulking the trough with silicon sealant and drilling a small drain hole, “being careful not to hit any wires.”
A number of members, starting with John Hoff, do not believe drilling a drain hole violates an item’s listing. Others agreed with creating a weep hole on a product’s underside, but only if the manufacturer supplies a suitably-sized knockout or authorizes the modification in some other way.
David was not able to examine the roof or basement facilities that day. Instead, he prepared a report that afternoon, accompanied by slides, which we saw at the meeting. The report included a description of the hazards represented by the various types of damage, and concluded that the panelboard no longer could reliably provide electrical safety. David described the risks associated with exposing a molded-case circuit breaker to moisture or, worse, soaking with contaminated water. (A cutaway image of a breaker was provided by Eaton’s Joe Fello.) This was useful: some present had not investigated the details of breaker construction, and were unfamiliar with the concept of the arc chute.
In addition to contamination of circuit breakers, busbars and ground bar, quite a number of the conductors in the panel had been thoroughly wetted, including a feeder. Lastly, the cabinet itself showed significant rust. Parenthetically, there even was evidence of rusty water having entered a receptacle outlet located several feet below the panel.
Throughout this main presentation, David called on sections of the 2006 UL/NEMA publication, Evaluating Water-Damaged Electrical Equipment . NEMA’s Code maven Vince Baclawski granted us permission to show excerpts, so long as we provided attendees with the information needed to access the complete text.
Now we turn to Joe Panizari’s further contributions. Joe had brought a picture of the roof wiring trough, on his phone. He showed it, and described it, as gasketed, albeit with a gasket that had lost a section when the cover was removed for examination. (Mark Nauman mentioned to the customer the benefit of "renewing seals and connectors, as part of regular maintenance. . .") The cover reached down over the body on all sides, which is sufficient to keep out rain that lands on it. Clearly it was outdoor-rated. Joe did agree with the engineer, provisionally, that water had entered the panel through the raceway going to the trough. However, he identified the raceway as EMT and explained that the water had entered it not from the trough but through a compression coupling below. Moreover, he noted that the amount of contamination and rust proved that water had been coming in to the panel for a long time.
Joe had not yet opened the wall above the panel to see what damage might have occurred in cables entering the top. He broached tentative plans for cutting back cables and for pulling new wiring.
We closed the discussion by around 7:40 PM, though Richard and another engineer continued talking about code issues a while longer.
The Code and the Standards, with UL's John Cangemi September 15, 2015
This is the record of our meeting with John Cangemi. He's been a UL representative, a New York City Electrical Board member, and CMP member and alternate over many years. In the following notes, he's "John." We had three Associate Members and three Inspector members, counting one who is about to join and would have joined tonight if we had the means on hand to sign him up immediately.
Chapter Vice President Karl Mirpanah started with an introduction of Robert Young, a very experienced Combination Inspector. Robert used to teach as well, but at 79 he finds the inspection work takes too much out of him.
Next, Secretary-Treasurer David Shapiro circulated the door prizes, which were donated by Garvin Industries. John commented that the breaker handle "locks" would not serve for Code compliance, as they do not stay with the panelboard (nor do these particular samples allow for an individual to padlock a breaker or switch handle). At the same time, he agreed that using these could be better than just informally tagging breakers. President Robert Welborne asked why they come in two colors. Karl confirmed that they have the same dimensions, so Rick Panizari speculated that maybe one is for emergency circuits, or maybe it's just that two different workers can mount the different colors. This way each can be sure not to accidentally remove a lock installed by the other.
On seeing the donated L-shaped boxes, John asked whether we were familiar with other special-shape boxes, an example being one that wraps under the edge of a joist. Johnny Hoff commented that with each section having the width of a utility box, these could not be set flush inside a normal wall.
Now David talked about our finances. We used to have a free checking account with Wachovia. This continued under the same terms for a long while after Wells Fargo took over Wachovia. Recently, however, their terms changed, making it too expensive to keep our account with them, given its very modest size. Members suggested we investigate various banks, which David will investigate.
A few minutes before 6 PM, John got going with the wide, wide, wide-ranging program. He handed out six copies of the very last printed edition of UL's White Book, which henceforth will only be available electronically. The 2015-2016 edition is already online and downloadable at www.ul.com/whitebook. Note that you have to enter it just like so. If instead you go to www.ul.com and search for the white book, you might have some difficulty.
John talked about how New York City finally progressed from using their own electrical code to adopting the NEC with amendments-fewer and fewer amendments, in successive editions. Why any amendments at all? Tradition, unions, and high population density. Johnny asked whether all electrical work is done by union shops. No, John said, generally not the small residential jobs.
New Jersey, he said, is about to adopt the 2014 NEC. They have a policy of allowing a contractor pulling a permit to choose whether to follow the newly adopted Code edition or the previous edition, for a six-month period after a change. Now it's true that you have to be consistent, rather than picking and choosing. In our area, which generally lags behind the latest edition, you can request permission to comply with a revised requirement that has not yet been adopted. Whether the AHJ will permit this is not guaranteed, but it is commonplace.
John promised that he would try to let us know which edition he is referring to as he discusses Code requirements, and he held true to this throughout the evening.
Johnny Hoff (in the following notes, he's "Johnny") asked John about how some GFCI receptacles have indicator LEDs that mean one thing, and some that mean another.
John agreed that there is no consistency, and it can be confusing. He brought up what he labeled as a personal prejudice. Voluntary, optional protocols-that isn't what he called them, nor do I think he used "standards"-can cause problems. He gave the example of BX with colored armor, the colors used to identify the voltage it's been installed to run.
Yes, you always should test rather than assume, and you should never work on energized equipment when it's safer to kill power. But people wink and work. So suppose a mechanic comes to the end of a coil of 12/3 BX coded for 277 volts, and it's the end of the day or the end of the week. What does he do? He sends his helper to the truck for whatever 12/3 BX he can find, so he can finish up the last 25 ft. Later, somebody comes along to work on the circuit, and notices the color code on the cable leading to the outlet or switch point where he needs to work. Assuming that it's 120/240, he takes chances he wouldn't take if he realized it's 277/480.
John's a very personal, and very entertaining speaker, proud of his Italian heritage. He told us that as a Brooklyn apprentice, starting in 1962, he had a lump on the back of his head. Why? His mechanic would whack him upside the head every time he screwed up. We saw a lot of the "don't give a damn" or "bubkes" gesture (flicking the invisible beard forward, "Me ne frego"), especially when he talked about the difference between a good mechanic and "a gorilla with a screwdriver."
Johnny, who in addition to his side business as a contractor works by day for Parks and Planning, talked about how janitors are directed to change lamps. However, they don't necessarily know they need to twist a bipin fluorescent, and they have not been trained to differentiate between, for example, a T8 and a T5.
The first piece John really chewed over for us was the designs and uses of MC cable, and the use of stamped donuts. Yes, these "reducing washers," Category QCRV, are suitable for use in grounding, both above and below 250 volts. The only exception is that they are not suitable for this use with service conductors.
John described all different types of MC starting with interlocked armor, type MCI; and interlocked armor with a bare grounding conductor outside the covering of the other conductors, tight against the armor, MCI-A such as Southwire's "MC-AP." The armor is not considered a grounding conductor, but in MCI-A the armor and bare conductor qualify as a grounding system. In this type, adding an insulated green ground qualifies it for use where an Isolated Ground is required.
David asked why you would use MCI-A rather than BX. One answer, from Rick, was price. Another, from John, is that MC is much less restricted as to the number and types of conductor it can contain.
Besides interlocked-armor MC there are exotic types: smooth armor, or continuous but corrugated. Their armor qualifies as a grounding conductor-but who's willing to pay the price for them? Coleman once made a type with a continuous but corrugated armor that had a square cross-section. John said it made for a nice-looking job, but because it required special connectors, and special care in cutting, it didn't sell.
There's also MC with an outer nonmetallic coating: "Deck cable." At first John said it could be used for direct burial if suitable for the conditions, but could not be used in a concrete pour. This was challenged, and John suggested a water and toilet break, so he could take the time to look it up in the White Book. He saw that MC listed for direct burial can go in a pour, and corrected himself.
About now Karl expressed his concern with setscrew connectors and couplings. Over time, it seemed obvious to him, they will get loose as a building shifts and settles. This is especially true when there is vibration, for instance where heavy trucks pass by. John agreed with him that these products may loosen, but at the same time assured him that experience shows this is not the problem one might expect.
Johnny asked whether, since interlocked-armor MCI, as opposed to MCI-A or continuous-armor MC, cannot serve as the grounding conductor, MCI could be installed in a nonmetallic box. Normally not unless it complies with Exception #1 or #2 to Section 314.3. David suggested that using a bonding bushing would allow it to be connected to the grounding conductors, fulfilling the requirement that, like most any metal equipment, it be bonded. John agreed that the idea seems plausible-but it's not Code-compliant, unless you meet the terms of those Exceptions.
Before the meeting, David had asked whether there could be a type of BX that contained communications cable. The answer to the question, as phrased, is no. Conductors smaller than 14 AWG are forbidden in BX However, MC can contain Class 2 or Communications conductors. It's called MCpcs. The low-voltage conductors must be separated from the power conductors by a sheath of at least 30 mil thickness. How did the committee decide on 30 mil? Because the sheath of NM must be at least 30 mil thick, and it is permissible to run communications cable and Class 2 cable in the same wall cavities as NM.
Robert now raised the specter of "phantom voltage." This is voltage induced by capacitive coupling. It won't show up on some meters, will on others. Johnny asked about "Super neutral" cable, which he once read about quite a fair bit in the trade press. Having a heavier neutral conductor than the hot conductors was intended, John said, to overcome additive harmonics.
Johnny also double-checked that his boss at Parks and Planning was right in his interpretation of the definitions of Branch Circuit, Individual, and of Receptacle in Article 100, and the interpretation of 210.21. John confirmed that with a multiple receptacle such as a duplex you do not have an Individual Branch Circuit, and therefore any fixed loads are limited to 50% of the circuit's rating. This, he suggested, is behind the common practice of supplying window air conditioners rated at not more than 7.5 amps.
Now John went to cable markings and temperature ratings. Modern romex is NM-B, whose conductors are rated at 90 deg C (and can be derated starting at that point) even though the cable can only be installed in accordance with the 60 deg C column in Article 310.
How about other cables used as NM? UF can be used as NM, but not single-conductor UF and not UF containing 75 deg C insulated conductors; it must be UF-B. And SE cable? If it is dual-rated as, say, SE and NM, fine. Otherwise, technically the AHJ has to provide Special Permission.
About now John put up a slide showing the history of NM. General Cable invented it in the 1920s, and Rome Cable (hence "Romex") manufactured it in the late 1920s. Besides NM, there's "NM-C," suitable for damp locations. That's NM-BC if it's modern cable containing 90 deg C insulated conductors. NMS is another cable that appeared in the NEC for a while, "Smart House cable," but it never was manufactured.
We spent a fair bit of time discussing Damp and Wet Locations. John was definite and clear about some environments:
Under a soffit? Damp. Not suitable for NM-B.
Over a tub or shower? Damp or wet, depending on whether water is likely to splash up high enough to hit the electrical equipment.
In a bathroom outside the tub or shower bounds? If it's just a sink-and-toilet (or -bidet) type bathroom, normally it will be dry. If it has a shower, the answer depends on whether it's going to get steamed up.
Inside concrete block? If the block is in an outside wall, and below ground level, normally it will be a wet location, because concrete is so porous. We didn't discuss block that's been sealed or parged on the outside, or that is filled with foam insulation that has, say, EMT rammed through it.
How about inside an outward-facing box in an outside wall, a box that serves a sconce? Technically, John said, it's a damp location, because any roughness in the wall surface will keep the canopy from sealing against it. The canopy-plus-luminaire system is only required to keep water from accumulating in the enclosure. A number of us discussed how we seal the canopy to the wall, at least on the top and sides. John told us that even though technically these boxes are at least damp locations, both romex and bx are permitted in them, due to so many decades of experience. Presumably this is true also of MC and of dry-location conductors in, say, EMT or greenfield.
Johnny raised the point that customers are troubled by deterioration of outdoor service cable sheaths over time. He's glad for the work replacing it, though it requires dealing with the local utility, and permits. Rick noted that water can get in through cracks in the sheath, and then travel into the meterbases and service equipment. David pointed out that even though the outside neutral wire wrap may not be damaged by sunlight, once the conductor insulation is at all exposed, it is not designed for sunlight resistance. He asked whether there is any paint that can be used to protect it.
John Cangemi said UL has not investigated any paints for compatibility with SEC sheathing. He noted that one acceptable option is to cover the SEC with vinyl gutter material. This improves the aesthetics of even intact SEC for many customers. It also shields the sheath from deterioration by sunlight, without putting it at possible risk as paint could.
NM cable, romex, does pretty well with most solvents, he said. However, if you spray insulating foam into a wall containing NM, the cable is exposed to a lot of heat as the foam cures. In one case, in New Jersey, walls were opened and NM was removed from where it had been locked in foam. The AHJ was asked to allow them to reuse it. Not an easy request. As with any product, its listing is valid until it leaves the factory. After this, the manufacturer and the testing lab have no way to know what it's undergone.
Who is the AHJ can be tricky. It's whoever makes or enforces the rules. Johnny talked about what a complicated thing it is to pull a permit in GHI, Greenbelt Homes, Inc. This is a cooperative housing project dating back to Roosevelt's New Deal, but coop or no, the occupants are the people hiring him to do the work. First he visits them and discusses the work they want, and discusses cost. Then they have to apply to GHI for a permit. Months can go by before this is granted. Then Johnny applies to the City of Greenbelt, MD for a permit and then to Prince George's County. By comparison, he told us, just obtaining the latter is "cake and ice cream."
Once he's done the work, both GHI and the County send inspectors; GHI's inspector sounded much pricklier. Johnny said that if an electric stove or dryer is connected to SEC, and you detach the SEC, move the stove, and reconnect the SEC--without either splicing on to the cable or even shortening it-GHI considers it new and requires you to run a 3-wire-plus-ground cable such as SER.
John noted that in this case GHI is an AHJ.
David double-checked: "But GHI is just the landlord!"
John confirmed that yes, not only can there be multiple AHJs, the landlord can serve as an AHJ.
At this point, having addressed a lot of questions that he knew we were interested in, John started going forward through various Code changes.
Discussing the background of Section 410.23, he noted that until the 2014 NEC is adopted, any combustible finish between the edges of a lighting outlet box and where the canopy meets the surface must be covered with noncombustible material. When he started in the trade, John would use rings of asbestos; later, of mica. Nowadays we can choose metal or some plastics. With the 2014 edition, the area under modest-sized canopies, something like 7x20 in. rectangles or 15 in diameter circles, is exempt. It seems that the measurement is the overall area minus the area of the outlet box itself, as that is not combustible.
He also pointed out that Section 410.74(A) requires that when needing more than 60 deg C conductors, a luminaire's conductor temperature rating is to be marked on the carton or tag, visible without opening. Under the UL standard, the temperature a luminaire conducts to adjacent building material is to be no more than 90 deg C.
One of the last few things John explained concerned the person who wants to run low-voltage wiring to power a luminaire. This is doable. Article 411, on Lighting Systems Operating at 30 volts or less now also covers lighting equipment connected to a Class 2 power source. Coming off a power supply fed by no more than a 20 amp circuit and Listed as and marked, "Class 2," which puts out no more than 30 volts (they tend to be rated at no more than 20 V) and no more than 8 amps, the installation now is legal, using, essentially, bell wire. It also can use communications cable.
In a brief discussion of electric signs, John made three points. First, installations of neon (and argon and other gases that glow in bright colors) are getting less and less common. Second, a sign does not have to have lettering to communicate. Third, zoning approval can be at least as much an issue as NEC compliance can be a concern for these signs,
The very last item than John covered before people started to leave is nonmetallic extensions, Article 382. Unlike romex, these were restricted to surface use and not permitted to pass through walls. (Since the 2008 NEC there is the possibility of listing a concealable type as well.) The extensions traditionally were designed with nail holes for mounting, and were used with self-contained devices. A major functional difference between them and romex is that the standard required them to undergo much more brutal testing. After all, can you imagine a nonmetallic cable whose manufacturer intended you to hit it with a hammer?
John had told us he was willing to go just as long as we wanted. Robert said he himself had to go by 8:30, and checked with our hosts that we could have the room till then. Well, John was as good as his word, and wrapped up just a little after 8:30. That wasn't it, of course. Karl had a question that he had put off till those who had to leave, left. And of course John was game to answer it.
Karl Mirpanah showed John where a Tom Henry inspection guide recommended against using EMT as a grounding conductor. Response? This is Mr. Henry's opinion. When you're inspecting you have to inspect in accordance to the NEC, not some other opinion or document that the NEC doesn't reference (e.g. in Section 110.3). Similarly, when you cite a violation, you must reference specific NEC requirements.
All in all, it was a hell of a talk.
This is the report of our meeting/tour on May 19, 2015. Two Associate members came, one Inspector Member, and one non-member. A second Inspector Member, brutally delayed by Beltway traffic, arrived as we were finishing.
The tour was scheduled for 5:30, and the four members who were not delayed arrived between 4;40 and 5:15. Timothy Haley, Director of Training for the Joint Plumbing and Pipefitters training center, said he was willing to stay with us as long as we wanted.
We did get a thorough tour. Before our group even started, Tim explained to Secretary-Treasurer David Shapiro that they chose low-flow toilets, but not the very lowest. Because these need to carry the waste further than toilets in, say, a high-rise apartment building, there needs to be more water to transport the solids. Later he talked about the system enabling them to collect non-potable water for flushing.
The bathroom sinks have no handles, but respond to motion or perhaps proximity. David mentioned his common frustration with the unreliability of these sinks’ sensors. Tim explained that often cleaning attempts smear the sensor windows, blurring their ability to see what’s out there. He also mentioned that their sensitivity is adjustable.
The hand-dryers use air blasts, Tim explained, because paper towels too often end up in toilets, clogging them. The dryer model they chose was definitely among the quieter ones.
As soon as we were four, we started the tour proper. Tim explained the solar water heating system outside, with reflectors concentrating sunlight on copper coils containing water with glycol added to prevent freezing. He reminded us that this is a far more efficient use of sunlight than is photovoltaic generation. When the solution in the coils brings the hot water system to the desired temperature, a low-voltage diverter sends the solution into other coils to radiate any further heat collected by the concentrators.
By 5:30 we went indoors and he showed us the gas lamps in the foyer, each in its brass-and-glass enclosure. A wall switch in the next room opens or closes solenoids and fires igniters. Each lamp also includes its own gas shutoff valve. Finally, each flame heats a thermocouple. If it does not signal that it’s heating, a solenoid shuts off its gas. All but the flame, thermocouple, and local gas valve is concealed by the brass behind the light.
Next we learned more about the building’s plumbing layout. Rainwater, he had said, is captured from the roof for toilet flushing. It feeds into a tank and, he explained in response to a question by nonmember guest Monica Cortez, P.E., a low-water alarm signals the need to shut a valve that diverts potable water into this system.
We stopped at a number of classrooms, storage rooms, and suchlike, occasionally commenting on light placement and choice of controls. (“Not a 3-way switch, hey?) Now we were shown the Mechanical Room, with its assortment of unusual machinery.
The rainwater comes down to a Vortex, where dirty water is separated from water suitable for use in toilet flushing. Chlorine is added as well as UV light treatment. Since the treated water that exits ends up outdoors watering the plants, there is some concern that the chlorine might do mischief–like draining a swimming pool onto the lawn.
We finished discussing the systems in the Mechanical Room in a few minutes. We spent a lot of time learning about the five-year apprentice training of plumber/pipefitters, as we traveled from a classroom to a room with a three ft deep sandbox–actually containing a clay mix, so they could dig in it without the sides falling right back in their hole or trench, and so they wouldn’t find themselves sinking. Tim joked that if they had really wanted to make the exercises realistic, there would also be old construction debris mixed in.
They are just as happy to take apprentices who have no plumbing experience, because it means they aren’t bringing any bad habits with them. They do want the students to have some ptitude for the work, and so they have to pass a two-and-a-half hour test–math, English, mechanical aptitude. It is administered by a testing contractor. Tim figures that the 5-year apprenticeship costs them about $35k per student.
The instructional equipment, stating with the computer-projector interface, will be new to many of their instructors, who will spend the summer getting comfortable with it–classes are scheduled to start September 15. More fitting out will still be taking place, but enough should be ready to get classes started.
We took a break here from learning about the building’s various instructional rooms and the union’s plans and climbed to the lower roof. Here we spent 10-15 minutes looking at the main photovoltaic (PV) array, a traditional design. Tim claims that the return on investment should take just seven years. In three years they plan to add lots more PV, on an upper roof.
We didn’t learn a whole lot about their PV design. The flat roof uses a resilient membrane material. The array is supported against wind lift, presumably, by having flat cinderblock placed on the metal. Asked about risk of the coarse weights rubbing damaging the membrane, Tim said the manufacturer of the roofing membrane approved its use with the system.
How did they choose the PV system? What maintenance was needed? Unfortunately, our guide didn’t have a very technical answer. Choosing various aspects of the building design was a three-year process. PV maintenance is limited to rinsing the panels; they should not be greatly soiled in the building’s environment. What if something goes wrong? Call the electrical contractor. Perhaps obviously, their electrical contractor was not represented on our tour.
After we left the roof, we continued our survey of specialized classrooms. We spent five minutes on the one for Basic Electricity. What does this mean? Circuit Boards. Hot water heaters. Garbage disposals. They want their graduates to be able to test for power at a hot water heater. What about PPE, David asked. Sure, of course, Tim told us. Well, what kind of PPE do they learn to use when performing energized tests? Tim confessed that he doesn’t know, not being involved in the instruction end. Monica asked him what kind of disposals he prefers, hard-wired or plug-in. Plug-in, definitely; but if their graduates have to deal with hard-wired systems, they need to know how to deal with them.
There was one section of the visit where we did examine electrical equipment, even though our tour guide didn’t give us any detailed description. That was the Electric Room. We spent a good 10 minutes there, looking at equipment and talking among ourselves. For probably the first time in the afternoon, here we discussed an NEC issue or two: President Robert Welborne pointed out that while there was a breaker rated at 1600 amps, normally bringing in a requirement for two exits, this is eliminated by the distance to the opposite wall.
Robert also suggested that the receptacle in the electric room, along with the receptacle serving the sump pump, might well be served by GFCIs. While Rich and David both agreed with this, they also said that they would not require it as inspectors. Prince George’s County remains on the 2002 NEC, and the two of us agreed that more recent requirements, as well as “oral code,” have no business creating red tags.
This was about it. And sadly, this is when our last Inspector member arrived. As we said our goodbyes, we asked a few more things about their plumbers’ training. They offer Continuing Education for their masters and journeymen, but taking the classes is optional for them in Maryland. In Virginia it is required. An apprentice needs 7500 hours of experience to become a journeyman, and then two years as a journeyman to become a master. WSSC (Washington Suburban Sanitary Commission, the area water utility) offers master certification that is honored reciprocally by Maryland and Virginia, albeit not by D.C.
The journeyman license is not optional for their students. For their apprentices to graduate, they need that journeyman license. They also need backflow certification. Finally, they urge them to get qualified for medical gases.
We left a few minutes after 7 PM, and chatted a while in the parking lot.
IAEI’s International Office granted 2 hours of CE credit to members attending this presentation.
"Reading Time-Current Curves for Fuses and Circuit Breakers," was our topic the third Tuesday in March.
Our March 17, 2015 meeting was attended by two Inspector Members, three Associate Members, and one nonmember in addition to our speaker and his associate. As in January and, we hope, for the rest of the year, we met at Classroom 1-2 of the PG Community College’s Westphalia Training Center at 9109 Westphalia Rd, Upper Marlboro, MD 20774.
We started informally at 5:40. At a bit before 6PM, our presenter, Eaton/Bussmann's John Kowal, EE, FAE asked whether we would have our business meeting first or have his presentation first. Secretary-treasurer David Shapiro explained that we would like to postpone our Annual meeting and election till after his talk, in the hope that we would achieve the needed quorum. Similarly, we’d hold any words about former chapter president Jim Wooten till the arrival of someone who might have known him well.
We began formally about 6PM. David brought up one business item now. Our chapter decided, years ago, that our representative to the Section meeting (normally the Secretary) will have Section expenses paid by the chapter. This was not fully possible last year, and probably won’t be this year. David held off any reimbursement last year pending possible further expenses, and now is prepared to reimburse himself $800 for last year, a little more than half the expenses documented. This $800 will leave $3-400 in the bank until we receive our next dues reimbursement from the International Office. David offered the figures for members to view. No one asked to look through them, and there were no objections to the reimbursement.
On to the program. John passed out stapled sheets with 17 pages of time-current curves and one containing a selectivity ratio guide showing the difference between different fuses. There was also a page with three exercises involving circuit breakers whose tripping curves we’d seen on previous sheets.
Throughout the evening, in addition to answering all questions, John repeatedly checked that we were with him in looking up the intersections of current and time on the screen (and presumably on the sheets on which it was duplicated), starting out by challenging us to do the arithmetic! He carefully walked us through looking up points on time-current curves, despite their being written in log10. Without being able to do this, we can’t compare overcurrent devices.
The current-limiting range of a fuse is 0.004 second, which is within the first half-cycle, i.e. 120th or 0.0083 second. The time measure at the very bottom of a regular Time-Current Chart is 0.01 second, a little more than 1/120th, above the current-limiting range.
The reason that a protective device’s curves consist of dual lines, with space between them, is that the left curve represents the beginning of its response to a certain amount of current, and the one to the right represents when it will have fully opened the circuit at that current level. If the space between the curves of two overcurrent devices overlaps, there is no guarantee which one will trip first at the levels of current where they overlap.
He noted that we need to be able to demonstrate coordination of protective devices. If the Time-Current Curves overlap, based on the short-circuit current that has been calculated based on assessed available current and upstream impedances, then the system does not coordinate. An alternate approach is to use manufacturer-attested combinations.
“Series-rated” tables are something different again. These simply ensure compliance with NEC 110.9, equipment having sufficient interrupting ratings.
Almost all fuses and circuit breakers are rated for continuous running at no more than 80%; this is why we multiply expected load by 125%. If a circuit runs hotter, the device degrades. Almost all? There are no 100%-rated fuses. There are some 100%-rated circuit breakers in the over-600 volt category. Important note: these require extra cooling space. They are used by data centers, which seek higher efficiency circuits.
“Where do we find the requirement to use protective devices within their interrupting ratings?” he challenged us. Not under Switchboards and Panelboards, but in 110.9.
His presentation wasn’t all numbers, curves and tables, either. His slides took apart fuses and John walked us through their design and that of electromechanical breakers, too. Fuses are filled with sand, which absorbs energy by turning to glass as it fuses. Sand is handy in part because it is surrounded by air, providing internal room for expansion.
Circuit breakers need to (1)sense overcurrent, (2)unlatch, (3)move contacts, and (4)quench the arc resulting from their separating. The older inverse-time circuit breaker contained one spring-loaded contact, but it tripped when the spring was overcome by an electromagnet that pulled this contact away from its mate. The newer dynamic-impedance design has each contact spring-loaded but acted on by an electromagnet. This separates them faster, reducing the duration of the arc. Arc energy is a product of current and duration.
When a utility has available 50k amp, this means an arc that reaches 115 peak kA. Even so, when a transformer reached no more than 125 kVA in the past there was not enough potential to arc badly.
A number of us, at least, were not familiar with the varieties of indicating fuse. Some fuses visibly turn black inside on tripping. Others have a strip of different metal visible outside, and heat breaking this is what demonstrates the passage of sufficient current to simultaneously trip the fuse proper. Or should.
Like pretty much anyone worth listening to in our field, John has safety on his mind. Some of these indications are not 100% accurate, he warned; TEST! Test your tester and then test the protective device that has indicated power interruption.
Your tester/meter, now, that is 99.9% accurate. So test your tester first, and then you can be fully secure that if it indicates a trip there has been no internal bridging of the tripped fuse.
Similarly, some breakers can indicate that they have tripped but actually have a frozen contact or frozen contacts. This is one reason that ALL breakers should be exercised. There is a paper on this, he said, by Dennis K. Neitzel and colleagues. (It can be found at http://www1.cooperbussmann.com/pdf/2352ccf4-8fe2-4062-98e3-e6336b695f5d.pdf).
A manufacturer’s Let-through chart reports what each fuse or circuit breaker will allow through of what the utility makes available.
When, despite the impedance of the wires leading up to a circuit breaker a fault close to its rating reaches it, it may not operate properly in the future.
A low-voltage power circuit breaker, unlike a dual-action molded-case circuit breaker, has no instantaneous response, however large the current. There is a problem associated with the operation of some circuit breakers with adjustable trip, meaning instantaneous trip ratings. For convenience, some electricians will extend the time delay of a circuit breaker’s instantaneous operation in order to reduce nuisance tripping. What they are doing is increasing the risk that the circuit breaker will no longer trip before the one upstream of it.
What you have here is just a taste of the day’s presentation. Outside the presentation proper, two other items were discussed. President Robert Welborne had a question, which he states formally here, as he presented it to NFPA:
I am a plans reviewer and the AHJ in Maryland. I am currently looking at a PM Pediatrics Center, (a night time urgent care facility for children only, not a defined hospital) where I am trying to get a more clarification about 517.18 C. As you are aware it states, “receptacles that are located within patient room…..……. shall be tamper resistant” I have spoken extensively with Mr. Jeffrey Sargent about this and he has given me his opinion. However, he advised me to reach out to the technical staff for more concrete written interpretation. My question pertains to the phrase “Patient Room”. Reading the informational notes under Patient Care Space, if correct, this Patient Room would include the exam rooms of this health care occupancy even though this area is not a Patient Bed Location? Also, what about the waiting area; which is sometimes filled with books, games and toys etc. for the children while they are waiting. Is that not now considered a "Playroom"?Robert added,
“The bottom line is the exam rooms would be included. I have not gotten a final ruling on the waiting room.”
At the end, a couple of us spoke briefly about the late Jim Wooten, former chief electrical inspector for Prince George’s County, former president of this chapter, and more recently inspector for Annapolis, till increasing disability took him off their roster.
Our next meeting will take place May 15, again at 5:30 PM. Presenter and topic will be listed here as soon as they are confirmed.
David Servine of the International Sign Association flew in from the West Coast to address our January meeting. It was a hell of a talk, covering Article 600 item by item, with examples and pictures; UL standards; the application of other NEC Articles; and even the forseeable changes in 2017.
The chapter secretary had to be out of town, and no member has come forward with written notes. However, thanks to assistance from Mr. Servine, we can provide the following overview of what he covered:
UL 879A, the Standard for LED retrofit kits
The Nationally Recognized Testing Laboratories accredited for signs--Met Laboratories, ETL/Intertek, UL, CSA, TUV, and Intertek's Werner Heiseck division.
the most applicable UL White Book categories--UYWU, Sign Conversion Retrofit; IFAR, LED Luinaire Conversion Kit, and QPTZ, Cable Types for Class 2. He noted that Type PLTC is used mostly.
The back to the NEC,:
Article 100 for the definition of RETROFIT; Article 210.4, MULTIWIRE BRANCH CIRCUITS;
Article 725, Class 1,2, and 3 isgnaling circuits.
He also discussed Public Inputs for the 2017 NECmodifying Articles 600.6(A)(1) and 600.33.
The presentation began about 6 PM and ended about 8:30. President Robert Welborne reports that no significant business was transacted. There were four Inspector members, two Associate members not counting our speaker, and one non-member.
January 20th's was our first meeting in a new, pleasant location: The Westphalia Training Center of PG County Community College, at 9109 Westphalia Rd., Upper Marlboro (Forestville).
Report of the November 18, 2014 meeting of the George Washington Chapter, IAEI
For the final time, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply, we met in their training facility in Forestville/Upper Marlboro, MD. Attending were three Inspector Members, four Associate Members, one soon-to-be Associate Member, and three non-member P.E.s, in addition to our speaker.
Can you get us access to a meeting facility? One at a generally convenient location, not too far from the Beltway, complete with a projector?
Vice President Karl Mirpanah again generously ferried our presenter to and from the premises.
At the end of the meeting, Secretary-Treasurer David Shapiro announced that future meetings, starting with our annual meeting on January 20, 2015, will take place at a new location that has not yet been selected. Aside from this, we spent no time on business, focusing instead on our very special speaker.
The January program will be on sign wiring, including Article 600 and plenty more, starting with listing requirements and common violations. Our presenter is an IAEI member who serves as spokesman for the International Sign Association.
Our guest was Jeff Sargent. He started as an electrician and then became an inspector in New Hampshire, and he still carries a license in New Hampshire and Maine. For the last 18 years, he has worked for NFPA; he served as NFPA’s go-to person for
His lecture started with . . . except that Jeff didn’t start with a lecture. He sat there with us and talked electricity and Code and safety. Ungrounded wiring, initially. Two-wire cables, and knob-and-tube, and how to educate inspectors who aren’t familiar with this. For instance, we noted that an external tester that requires a ground reference won’t work. This means that if all an inspector knows is to rely on the tool, they can fail legitimate work that the tool isn’t equipped to deal with.
Then we talked about water-based shocks, electrocutions, and drownings. What level of protection really protects swimmers: 30 mA, 100 mA, 4-6 mA? How about shocks from plumbing? A number of us have felt them. Jeff’s take: if everything’s installed right, the shock shouldn’t happen. On the other hand, if the service-utility neutral connection loosens, all sorts of problems can develop.
One area of content that we had agreed on ahead of time was that we’d leave plenty of room for questions. Still, a little before 6 PM we asked Jeff to start presenting the material he had formally put together for us. This means that after giving us the little bit of biography you saw two paragraphs back, he talked about NFPA. Their mission? They work to save people and property.
He asked, “Any of you here smoke?” No one. He explained that improperly-extinguished cigarettes are responsible for so many fires, so many deaths and horrible burns, through setting upholstery and bedding on fire. NFPA and its partners fought for national standards to require self-extinguishing cigarettes, but the tobacco interests fought them. They weren’t stopped by this--they went state-by-state, and got laws passed in 50 states. NFPA also is fighting for home sprinkler requirements, and for the same reason. These result in vast savings in lives, #1, plus greatly reducing most big injuries and property damage associated with home fires.
NFPA also works hard to promote public safety in other ways. They sponsor National Fire Prevention Week, the week of the Great Chicago Fire, which killed 300 people in 1971. The Week has been honored since the days of Woodrow Wilson.
We moved on to the
Based on Section 90.1, we know from the start that NEC compliance does not mean ideal performance. Here’s an example he gave in the realm of selective coordination. Protective devices in health care facilities must be coordinated to within 0.1 second in the hospital proper; in any associated assembly occupancy, though, they must be fully coordinated. If you are running a hospital, you might prefer consistent protection across occupancies; this is beyond what the
Sad to say, some places in the U.S. are woefully behind in implementing the Code. In our own chapter, editions enforced range embarrassingly between the 2002 to the 2011. This is minor foot-dragging, though, compared with Mississippi. They have no electrical licensing, very scattered enforcement, and correspondingly bad levels of electrical fire, shock, and electrocution. With the recent hurricane damage, finally, FEMA came in. FEMA is requiring the adoption of building codes statewide. Whether suitable enforcement will be established and funded is to be seen.
The problem is that people just want electricity to work. Until there’s a tragedy--or a near miss–the average Joe isn’t so interested in legalisms. Jeff could testify from personal experience that losing electricity can really crimp your style. Perhaps our being a relatively intimate gathering encouraged such a rich sharing. In 2008, a storm knocked down a power line near his home. Because the power serving so many others also was lost, this wasn’t a matter of calling the electric company and getting them to send a crew right over. He spent 11 days without utility power, so Jeff is in a very good position to talk about how it feels to be without reliable power coming in through your meter and serving all your appliances–even without injury or fire.
There are other standards that come in to play when we want to apply the NEC. Jeff listed a few of them:
Next Jeff talked about
Johnny Hoff wanted to know whether commissioning is included in their scope. No, Jeff said. In fact,
You’ll also find Errata at that NFPA site. These pure and simply correct mistakes. So they are incorporated into the following code editions. David piped up to ask whether Errata have any importance. Jeff acknowledged that usually they just correct internal references and suchlike, but occasionally they do count. He gave an example from the current edition. The 2014 NEC Section 680.25 lists an exception to the rule that feeders serving pools must contain insulated grounding conductors. In 1-2 family occupancies, an exception for covered grounding conductors had been present in the 2008 edition, removed in the 2011, and apparently restored in the 2014. The restoration was a mistake: an Erratum tells us there’s no more exception.
Jeff mentioned that some large states are still only on the 2008 NEC, which was embarrassing for some of us in the room, still working under the 2002. Jeff asked us whether anybody had submitted proposals for the 2017 Code, and several had. He wanted to know how we liked the new on-line procedure; we like it fine!
We moved on to another item that’s not part of the main Code text. Some might think that Informational Notes (formerly FPNs) could be easily ignored, since they don’t contain mandatory NEC rules. Well, then Jeff threw a picture of a fire pump on the screen, and asked us how you calculate the overcurrent protection for the conductors feeding it. Folks didn’t do too badly. Dino Panizari chimed in, and Harry Langway, and we got the answer clear: size it to handle the pump’s locked-rotor current indefinitely. Okay then, where do we get the locked-rotor current?
There’s an Informational Note to
President Robert Welborne asked a question here about the legality of feeding jockey pumps from controllers, and Jeff steered him right.
Now Jeff threw another slide on the screen, and asked this question: how would you classify this woodworking shop? Okay, combustible dusts, maybe. But they have to be fine enough to qualify, he explained. Maybe they’re flyings, instead. It’s a matter of how many microns, what mesh filter they could get through, that will determine the category. In response to a question he said no, it’s not necessarily obvious to the eye.
Robert Welborne mentioned a recent case where he classified a woodworking manufacturing occupancy to be listed as a class III location. However, after conversing with a few fire engineers he changed a portion of the building to a class II location. Jeff called this a good example of how some occupancies can have multiple classifications.
NEC Article 500 does not reference NFPA 664, which is where you need to go in order to determine the classification. Volume of cutting debris produced and housekeeping are also factors. The picture he had up showed a squeaky-clean woodworking shop, with an exhaust system picking up from each work station. (My initial take on the picture was that it showed a new shop, never worked in.) He brought up a few lines of NFPA 664 to the screen, and pointed out an unfamiliar feature. In every NFPA standard but the NEC family (which put Informational Notes in the text), if there is an asterisk by a line it refers to a note in an Annex, providing non-mandatory information useful in applying that line of code.
Moving on, Jeff talked about the value of NFPA 70B, the Maintenance Code. Does equipment last forever? People want it to. He asked, rhetorically: do they perform any maintenance? David pointed out that some people replace their smoke alarm batteries when they set their clocks forward and back. Aside from this, though, he reiterated: what does anyone do? Who tests their smoke alarms and their GFCIs monthly as instructed by the manufacturers? Yet we know that switches such as circuit breakers need to be exercised. He put it to us: what PPE would we need to operate the handle of a switch that had not been exercised for an indefinite amount of time? Now we’re thinking in terms of NFPA 70E. Okay, he proceeded: suppose it was outside, rather than indoors? 200 VAC, okay, if there wasn’t evidence of rust, but how about higher voltages? What PPE? Earlier, he had emphatically reminded us that the standard designates PPE not as what you wear to do a job so as to avoid turning off power and inconveniencing everybody. It is what you wear to do a job only in two circumstances: one, where the nature of the job requires working on energized equipment, for example some troubleshooting; two, where killing power to the equipment creates a greater hazard, perhaps elsewhere in the building. P.P.E. is not for use to avoid some higher-up such as the building manager or factory owner throwing a fit.
More questions: David asked whether NFPA 70B has any guidance for outdoor equipment that normally, over time, is infested with insects, due to their access through weep holes. Jeff didn’t have a direct answer, but noted that its Annex lists the recommended frequency of many maintenance operations. [This starts, it looks like, with Annex K–and a number of pages into it, if you’re talking about equipment such as molded-case circuit breakers]
The discussion went on to explore types of equipment that members have seen disabled by insect infestations. Johnny works for Parks and Planning, and he talked about GFCIs in buildings serving tennis courts, rarely used and not very accessible, that commonly are trashed by insects. He wasn’t the only one. Jeff says you find this all over the country. Dino asked about whether better-sealed equipment is immune to this. In response, Jeff noted that birds’ nests on top of heat-producing equipment such as outdoor luminaires have caused fires. He also pointed to rodents, which enter houses wherever they can and gnaw on cables and conductors. His in-laws lost power due to squirrels that had entered their attic. Fortunately, they created enough of a short to trip the overcurrent device.
Throughout the evening, David and Harry each had been asking questions about marinas and boats. Jeff had talked about the ongoing dialogue between the American Boat and Yacht Council (ABYC) and NFPA, mentioning ABYC’s November paper for the Fire Protection Research Foundation comparing protective devices at marinas. Another non-
Jeff moved on now to solar energy, and Section 690.12, Rapid Shutdown of PV Systems on Buildings. This is for the safety of firefighters. How is anybody expected to comply with a requirement when there’s no equipment to fit the bill? Well, we’ve certainly managed to address anti-islanding requirements for utility-interactive systems. In fact, Jeff confided, a system has been listed, just recently, that fits the bill for 690.12. Jeff is preparing an article for NFPA Journal on this issue. Jeff said there’s a new direction being explored for 2017: treating module support structures as lightning arrays. After all, they’re grounded metal structures distributed over roofs. How about adopting the use of their grounding conductors as lightning down conductors, if that’s a purpose they actually may serve, whatever our initial intention for them?
David asked whether the people who want to promote lightning advance streamer dissipation have gotten any traction for their own Standard or for inclusion elsewhere. Jeff said that the place for them would be within
One of the last items that Jeff addressed--at our urging–was anticipated changes for 2017.
We moved on to DC. Now Jeff brought up the issue of grounding a system that includes AC and DC, where the DC, normatively, used Red as positive and Black as negative. The standard approach is to ground the negative, but Jeff suggested that there may be occasions when it is better to ground the positive conductor. Suppose you transition from individual conductors to a cable containing a black and a white conductor. Do you want the black to be the grounded, the white the ungrounded conductor? Nuh-uh. Do you want to connect the open black to the cable’s white, the open red to the cable’s black? If we set it up so DC positive red is grounded and DC negative black is ungrounded, then connections between cable and open conductors are much less worrisome.
There is a task force doing a gap analysis of the
There is another task group looking at the question of “physical damage” and “severe physical damage.” Proposals in several Code cycles have urged making these terms more specific. [This is happening despite the fact that they are not among those singled out as vague in the NEC Style Manual--http://www.nfpa.org/Assets/files/AboutTheCodes/70/NEC_StyleManual_2011.pdf]. Another task group is looking at the requirements for Equipotential Planes and Bonding in 547.10, 680.26, and 682.33. Shouldn’t they line up? Wayne commented wryly that we take better care of dairy farmers’ milch cows than of swimmers.
Another considers GFCI protection. We find it all over the Code. Sure, it’s in 210.8. But then it’s in 210.13 for circuits over 1 kV. It’s required for boat hooks and dishwasher outlets and gas station vending machines. How about ensuring consistency? Maybe they all belong in a separate article? We stopped just a couple of minutes shy of 8:30, because our host asked us to clear out by 8:30. The notes you have read might convey, oh, half of what was covered. Jeff Sargent is incredibly stalwart, and was one of the most cordial as well as knowledgeable speakers we have enjoyed.
Report of the September 2014 meeting of the George Washington Chapter, IAEI
Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply–and his staff--we met in their training facility at 8511 Pepco Place, Upper Marlboro, MD. Attending were two Inspector Members and five Associate Members, in addition to our speaker.
Vice President Karl Mirpanah, who ferried our presenter to and from the premises, opened the meeting at 5:40, as President Robert Welborne was away helping his grandmother celebrate her 100th birthday.
The first regular report David Shapiro gave, as our treasurer, was on our healthy bank balance. Last year and so far this year, we have avoided spending anything except the very modest fee our bookkeeper, Pam Panizari, asks for our annual audit. Therefore, the bank account has everything we received this year from the International Office, plus. Part of this will go toward future payment of our bookkeeper, and the rest almost certainly to reimburse expenses for our representation at the Eastern Section meeting. Records, of course, will be kept and submitted.
As Secretary, David reported that quite a few members have been receiving our notices by snailmail, either because their email had bounced or because even the International Office doesn’t have edresses for them. Only one or two of them have shown up at meetings. In the last few such mailings, he had asked members for whom we don’t have working email addresses to either confirm that they are interested in continuing to receive notices sent via the postal service, or to supply valid email addresses.
So far, one such member, John Carignan, arranged in response for email from the chapter to be whitelisted. In fact, he was present at this meeting, his first! Two members indicated that they want to continue receiving snailmail notifications. One of these, sadly, mailed a note saying that health reasons prevent him for attending meetings for the time being. On further contact, he said that unfortunately finding him a ride would not help. He had sent in a contribution with his note: a number of Forever stamps. Inasmuch as he does not seem to have Internet access, and IAEI News no longer prints Secretaries’ reports, we’ll use those stamps to send him a printed copy of these meeting minutes.
If any members reading these minutes have colleagues who mention that they are puzzled that they have stopped receiving notifications, please ask them to get in touch.
Another item: For those members who use, or are interested, the 2015 edition of NFPA 70E is now available for reading–free–to anyone visiting www.NFPA.org. Our speaker commented positively on it. He also mentioned that the free Code access at WWW.NFPA.ORG includes NEC amendments, proposals and comments going way back, but offers the full text only for the 2011 and 2014 editions.
The business portion of our meeting concluded, we went to the eagerly anticipated Education program.
Jack Lyons, hailing from Western Massachusetts, has ably taken over as Northeast representative for NEMA, the National Electrical and Medical Equipment Manufacturers’ Association. (Medical? For the many years that Gil Moniz held the NE rep position, the acronym just meant the National Electrical Manufacturers’ Association. Same organization; though other outfits do use the same acronym.)
Jack began with general information on NEMA’s activities and, especially, its publications. For example, they are part of the movement to encourage adoption of up-to-date Code editions. Example: although our meeting place, Prince George’s County, Maryland, is still rather behind, Washington, D.C. finally moved up to the 2011
NEMA standards are all available for download or ordering, and the list of standards, with descriptions, is available online. Some of the standards are downloadable free; others cost. Could looking at a standard help an electrician decide whether a product is bogus? Well, maybe. UL publications are more likely to be the useful resources for when you suspect a counterfeit.
NEMA’s publications include both ANSI standards and recommended guidances. In addition to handing out copies of the two brochures he reviewed at this meeting, Jack offered to send copies of Storm Reconstruction: Rebuild Smart to any member who was present and doesn’t care to download it. This afternoon and evening, the NEMA publications he focused on were not standards but guidance documents. His first focus was the brochure on “Evaluating Water-damaged Electrical Equipment.” The second, brief talk reviewed the brochure “Evaluating Fire- and Heat-Damaged Electrical Equipment.” These are not the law of the land. FEMA, the Federal Emergency Management Administration, has made use of them, but jurisdictions accept and utilize them to varying degrees. Each one does contain multiple references to NEMA standards for types of equipment.
In a nutshell, so much equipment needs to be discarded, but not all. Rather than focus solely on the printed text, Jack explained its recommendations and gave examples–some pretty sad. Why discard so much? Because the equipment might still contain water, because the water that reached it may have contained contaminants, because electronics are bound to be trashed, because springs may change their tension: innumerable flaws, both visible and hidden ones. Some show up as soon as the equipment is put into operation, if it can operate; others take a while to manifest. “Get a GFCI wet, and you’ll be lucky if it lasts a day.”
One example of not discarding showed a small foolishness punished with a substantial loss. A homeowner had recovered his portable radio, which had been floating in the flood water. He plugged it in, and happily it worked! He set it going in his garage and stepped out for five minutes. When he returned, this incendiary had set his house on fire.
But how come his electricity was back on, after his house was flooded? Maybe an electrical inspector had made a careful determination that his service and many of his circuits had remained dry and safe. We weren’t told about this particular instance, but in many cases power was turned on recklessly. Instead of bringing in electrical inspectors from elsewhere in the country who would have been happy to come down and help to evaluate the safety of electrical systems, Long Island towns turned to canine control officers, motor vehicle officers, anyone they had on staff. In many other cases, utility workers turned power back on to whole sections without any go-ahead from local inspection authorities. One inspector told him that if they lose only one house to fire by bringing the juice back to 1000 homes, he’s good with it. All too often, electrical AHJs were given at most the power to advise but not to dictate. No teeth.
Even competent inspectors were reluctant to demand rewiring when homeowners were back living in their houses.
What about electricians? Some of them just refused to set foot in a house where the homeowner wasn’t prepared to change out wiring that had gotten wet. They had good reason. Suppose there’s a scratch or a pinhole in the jacket of romex. Water will enter, travel all the way down, and wick its way up for 7-8 feet. David asked about meggering. Fine, for a snapshot of right-now insulation function. But. Pete Bowers chimed in with a few comments here. Suppose the insulation gives a fine reading now. You put the cable back into use. Sooner or later the current flow generates heat, and any moisture that entered and traveled along turns to steam, ballooning the jacket and possibly causing further insulation damage.
Then there’s staples. Jack talked about how nobody is taught what it means to nail in a staple “securely.” If the staple is tight enough there’s no give, so the cable can’t slide under it, then when the wood against which it holds the cable swells, it’s going to squeeze and squeeze some more. David commented that NEMA recommends the use of staples with a plastic barrier between the crown and the cable. Jack dismissed this as not making a difference where the staple is nailed in tight: extreme pressure pulling on any staple, insulated or not, may overcome the cable’s integrity. David came back and asked about the standard Canadian staple, which isn’t made of narrow wire but of flat cut metal, and moreover has a stop on each side to keep it from being hammered–or maybe even pulled?–in too far. Jack let this one go, because he’s not familiar with the Canadian design. How about UF? From observing the use of UF in agricultural buildings, Jack believes it is more robust.
Metal cable? The jacket rusts and at the least loses continuity. Consider BX. If we’re not talking about BXL/ACL but modern Type AC cable, there’s a thin internal aluminum strip against the inside of the spiral armor to overcome inductive impedance. It dissolves.
Surely equipment designed to go in water should be safe, right? Maybe not right. Normal wet-location equipment such as a conductor with a “W” in its name is not tested for protection against salt water, just clear. There’s another twist, though, when it comes to equipment. Usually only one end of a product’s cord is designed for immersion. Sump pumps have failed because water got into their cords, traveled down inside the submersible motors, and shorted them out. Wet niche pool fixtures have been filled with water that took a similar path.
The brochure says that it may be possible to recondition cables, but really, Jack explained, all you can do is inspect them to see whether they remained dry.
There is equipment that clearly can be reconditioned. If the NEMA standard and manufacturer’s standard instructions specify maintenance procedures, you may be able to take apart that motor control center or that circuit breaker, and follow those approved procedures to replace parts and put it back together again. “Really? Circuit breakers?” Dino Panizari asked. Well, Jack said, he’s never seen a maintenance standard that covered a circuit breaker rated less than 400 Amps.
How about motors? A motor guy told Jack that he didn’t mind the steel laminations getting a little rusty–rust helps insulate! On the other hand, he couldn’t wash the salt off coatings however much he doused them; couldn’t, that is, until he mixed in dishwashing soap.
Overall, though, thorough wetting–or, we learned, heating or smoke exposure even without exposure to fire suppressants–means a lot of replacement. When New York City got dunked, 70% of the switchboards in lower Manhattan got changed out. The advice in the 12-page brochure, “Evaluating Fire-and Heat-Damaged Electrical Equipment,” closely paces the one on water damage. Even the tables on replacement versus reconditioning are very similar, with just a few items that may survive soaking but not heat and smoke.
Many people who should have this information, unfortunately, don’t understand the need for the measures it recommends. Jack learned at a recent Rhode Island meeting on the National Grid that all too often, spreading knowledge means informing one contact person from each jurisdiction or department. This often fails. That one-person dissemination needs to be followed up to make sure that the contact persons in turn spread the word to all within each jurisdiction.
The slides Jack showed weren’t limited to booklet tables or pictures of fire- and water damage. He also showed solutions. Some solutions turned out to be a lot more complicated than people thought. Raised foundations is the one Jack mentioned, and showed in a slide. Suppose the (newly recalculated) 500 hundred year flood plain, which yields the potential high-water mark for a flood, shows that your foundation could end up eight feet under water. An obvious solution–at least if you’re not in Holland, we presume–is to start laying block until your rebuilt house’s foundation rears at least eight feet higher than before. However, you may not have accounted for the potential hydraulic pressure. Water is heavy and its movement can be powerful; it could cave in your foundation. So you have to include valving or gates to let the water through.
Considering how long this description of the first talk is, you probably won’t be surprised to learn that he had to speed through the last part. Even so, and even though he’d been talking to the group for so long–and talking with a couple of officers for an hour or two even before his presentations–Jack made time for a good review of the development and content and materials associated with the evening’s second major topic, Low-Voltage Suspended Ceiling Power Distribution Systems.
The ultimate basis for this new article is the fact that so many devices that rely on batteries or on DC power supplies. Distribution of DC power, at least within a building, could result in many efficiencies. A group called the Emerge Alliance was formed with the mission of developing standards leading to the rapid adoption of DC distribution.
They proposed something very much like 2014's Article 393 in the previous cycle. Then, the proposal was rejected–the products were all too new and untried--but they were encouraged to return. And they succeeded. The location of the new article in Chapter 3, and Code-Making Panel 18's responsibility for it, may both be different in the 2017 Code. Meanwhile, the components are available, and the systems are being installed–in a few places so far. Consequently, our contractor members may just end up invited to consider taking on the installations; our inspector members may just end up with them on their inspection rosters.
The basic concept, as it is being offered now, involves ceiling support grids that incorporate exposed, power-limited low-voltage DC busbars. Power supplies are attached to them through matching clips. Individual 6-12 ft. grid rails’ (T-bars’) busbars can be mated end-to-end, but this does not interlink their busbars. These only can be extended by using jumper cables incorporating matching clips. Each item of utilization equipment is sold with a cable and clip to mate with the appropriate busbar.
Who installs them? Ceiling installers are not authorized to wire them, just to hang the grids. The grid rails of the power distribution system are main members, and they are very clearly marked to indicate the holes needed for clip polarity maintenance, as opposed to the slots that are to be used for the hanging wires. These rails are designed so they do not reach all the way to the walls, by the way. There are short no-busbar sections designed to clip onto the ends of the power-distribution rails to support the ceiling panels the rest of the way to the edge.
The electrician hard-wires the power supplies, which are mounted above the ceiling. He installs a separate feed cable for each DC circuit coming out of the supply to a T-bar. Each feeds a maximum of 100 VA load. This is self-monitoring, -limiting and -restoring. He installs any jumpers, and the cables feeding the utilization equipment. All these cables are attached to the grid using special clips, not to the hanging wires.
The Class 2 power supply’s monitoring and self-isolating protects the electrician from getting stung through inadvertently touching both polarities of busbar at once. It also protects against reversed polarity, and protects against inter-circuit contact. It is capable of sending remote status alerts, of coordination with energy-monitoring systems, with various control systems–including in some cases separate control of its individual DC output circuits--and of working with alternative sources of energy that might supply it with DC.
There normally will be many such power supplies above a ceiling, each designed to feed a certain number of output circuits. The controller that feeds them is in turn is fed by a multiwire circuit, whose disconnect must interrupt both the energized and grounded/neutral conductors.
There was more, but this was as much as I recorded. Jack concluded his presentation about 8:20 PM. He had been on-site readying for and then presenting his two CEU-hour program for at least five hours. After we expressed our appreciation, a motion to adjourn was moved and seconded.
Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply, we met in their training facility at 8511 Pepco Place, Upper Marlboro, MD.
Attending were two Inspector Members, four Associate Members, and two nonmembers, in addition to our speaker and his colleague.
The business part of a meeting consists, at minimum, of officers’ reports. President Robert Welborne did not offer a report. To avoid delaying our speakers, the first regular report David Shapiro gave, as our treasurer, was on our healthy bank balance. So far this year, we have avoided spending. Therefore, the bank account has everything we received this past year from the International Office to go toward, first, paying our bookkeeper; second, our representation at the Eastern Section meeting. David’s second report, as Secretary, was on member welfare. Long-term member Pete Bowers is recovering from a stroke. His recovery has been impeded by the development of gout in both feet. He had talked about taking on the responsibility to serve as our Membership officer if he was well enough. That is not going to happen.
David didn’t report the outcome of our election. However, there’s no reason not to give it here:
Robert Welborne continues as President.
Karl Mirpanah is now our Vice President.
David has been elected to serve another year as Secretary-treasurer.
Other offices remain vacant.
The business portion of our meeting concluded, we went to the anticipated Education program not long after 5:30.
We were pleasantly surprised to discover that Dave Monka, our area's Bussmann District Sales Engineer, had invited John Kowal, Field Applications Engineer, to join us and to offer the advertised presentation on selective coordination and modern fuses. John has been with Bussmann for 27 years. We wanted technical information specifically about selective coordination for compliance with NEC requirements. Dave felt that despite 27 years with Schneider/Square D and then Eaton, he himself wasn’t the best man for this job. We’re grateful to both Dave and John.
John started out offering a 110.26 app for the IPad and Android. Scan the card he distributed and you can download a tool that will give you available fault current at the time of your installation.
After making sure we understood the meaning of selective coordination, John’s first challenge was this: why is this required for emergency circuits? The answer lies in NEC Sections 700.28, 701.26, and Articles 708 and 517.
Next, John laid out his talk:
What are the guiding Code requirements?
Why is Selective Coordination important?
Which overcurrent devices need to be selectively coordinated?
How can you comply?
What are the costs and tradeoffs associated with complying?
Finally, what myths are connected with selective coordination?
I can’t hope to offer you more than a glimpse of his presentation here. If you want more, perhaps you might have an opportunity to learn from John at an IAEI Section meeting. While he’s not slated to give a presentation at the forthcoming Eastern Section meeting in Annapolis, perhaps you can find him as a Cooper-Eaton-Bussmann representative. Anyway, on with the show.
We’ll end these minutes with the example John used, emphasizing the importance of selective coordination to power users who consider their loads important to keep running, regardless of whether the NEC requires it. It helps minimize the loads affected by an electrical outage, and that is important for more than just life safety.
That’s theory, albeit important theory. As he addressed the items in his outline, John didn’t keep us waiting for practical pointers.
The major fuse manufacturers, he said, publish selectivity ratios whereby you can choose fuses that provide coordinated protection. However, he emphasized, you can’t mix fuses by different manufacturers and hope that the coordination between one size and another will hold just because they match the published ratio, and more than you can mix different circuit breakers with impunity. “Will fit” is not way to select protective devices. The impedances are different.
With circuit breakers, achieving coordinated protection is not so easy. As they age, any ratio that was initially valid might change. You need to rely on short circuit studies or on tables.
Breaker manufacturers perform short circuit studies mapping response at particular fault values. They test combinations of breakers that can be used to achieve coordination safely. As you consult these tables, here again you can’t substitute other brands that were not included in the tests.
How about coordination of fuses with circuit breakers? Just as with fuses, someone would have to test. Eaton has tested and shown that certain Bussmann fuses can provide coordinated protection to certain Eaton brands of circuit breaker. Other manufacturers, too, have published the results for their brands.
A few asides from John:
An Automatic Transfer Switch has a specific Close-on withstand rating, and its listing will specify what fuses or circuit breaker to use with it.
NFPA 70B gives maintenance requirements for circuit breakers.
What is involved in picking Insulated Case circuit breakers for selective coordination?
Where the options for coordination might be instantaneous trip, short time delay and long time delay, there’s a problem with using either of the delay settings. If a customer complains of “nuisance tripping,” and in response an electrician lengthens the delay, he might be throwing design considerations out the window. John showed us examples of using time-current curves that have been published for instantaneous trip responses to select breakers that can be relied on for selective coordination. An alternative, he noted, is to use tables that give reliable pairings of breakers.
He laid out a formula that is used as a rule of thumb for selecting circuit breakers for selective coordination, based on instantaneous trip values. The maximum overcurrent for selective coordination is approximated by the circuit breaker’s amp rating x its instantaneous trip rating x (1- its percent tolerance)/100%.
John had made several points concerning the advantages of fuses for selective coordination. He nailed them home by mentioning some data centers chosen to follow the rules for Critical Operations Power Systems. They just redesigned their distribution systems from relying on breakers to fuses, in order to ensure coordinated protection of their business-critical loads.
Afterword: when I asked John to glance over these minutes–thanks, John!--he made the point that what he was talking about with us was coordination (selective). “What’s the significance of this,” I asked. The NEC’s selective coordination, he explained, extends over the range “from time zero during the high-short circuit region through th overload region (basically at .01 seconds).” The NFPA 99 (Health Care Facilities) version coordinated protection more in the overload region, 6 cycles or 0.1 seconds–“virtually a lifetime when you want to interrupt a fault,” as he put it.-end-
Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply, we met in their training facility at 8511 Pepco Place, Upper Marlboro, MD. Former Chapter President Wayne Robinson was presenting an afternoon seminar in the same building. (The seminar was not associated with IAEI.)
In the picture, Ken sits at the menhir directing each knight (of the electrical industry) who enters the building to take the path to the right, leading to the seminar, or to the left, leading to our meeting. One Inspector Member and three Associates braved the latter path.
Chapter President Robert Welborne had to skip this meeting. He was out of town because of a death in his family. Johnny Hoff informed us that he too had suffered a great loss: his brother died in February. The man had been ill for some time but toughed it out. When he eventually went to a doctor, it was too late to control his disease.
Johnny’s father had a similar attitude, and had suffered a similar fate. The reason for bringing this up in our meeting notes is that the only good thing that can come out of this misery is if someone sees the story and maybe makes a different choice for himself or his loved ones.
The usual business of a meeting consists, at minimum, of officers’ reports. The special business of this meeting was to be the annual election postponed from the snowed-out January meeting.
Because we fell so shy of a quorum, we delayed our meeting start from 5:30. In the meantime, Johnny Hoff talked about his brief vacation in Guatemala and shared pictures.
Close to 6 PM, David called the meeting to order as a proxy for our President. We talked very briefly about the chapter election, which now will take place online and by mail. Robert Welborne had informed us that he is willing to continue as President, and David Shapiro is standing again as our candidate for Secretary-treasurer and Chapter Representative. With a little encouragement, Karl Mirpanah agreed to run for Vice President.
David also mentioned that in his next snailmailed chapter notice, he will ask recipients to notify him if they are interested in continuing to receive such notices. This way, those who don’t opt in to receive them through the postal system no longer will do so.
As a result of some mysterious mixup, the presenter listed on our schedule did not arrive and did not notify us that he would not be coming. So we picked each others’ brains about inspecting and troubleshooting.
First Karl described an installation he had to red-tag. It was a very tidy installation, but the connections were wrong. First, three-phase circuits were protected by single-phase breakers with handle ties. Second, for some unknown reason, phases A and B of the first circuit would be connected to the first two busbar spaces and tied to a conductor of the second circuit fed by the breaker in the third space; and so forth down the line.
It took a while for us to understand just what Karl was describing, but once we did we all were puzzled as to why the installer had done this. Equally puzzling is the fact that Karl reported that instead of saying, “Whoops! Thanks for catching that; I sure goofed,” the installer tried to protest that what he had done was fine.
Next, David talked about a puzzling residential layout he had seen earlier in the day, in a century-old house in DC. First, the context. A room had smelled of burning, and after disconnecting the circuit serving it, the homeowner had called him out on a rush basis. He found that there was no such smell associated with the room’s two receptacles, and their wiring showed no signs of having been singed. (One was a duplex device with the single-pole snap switch controlling the chandelier.) However, of the suspended chandelier’s three lampholders, only one had been replaced and was in use; but another did have a burnt smell. While unlamped, both the non-replaced lampholders had remained energized.
There was no burned smell at the canopy either, so David proposed disconnecting the non-lamped lampholders to see whether that ended the problem. However, the homeowner opted for his removing the chandelier entirely, so she could get it rewired.
None of this made the job worth bringing up at the meeting. Here’s the puzzler. David checked the leads at the canopy to confirm polarity before killing the circuit and connecting a temporary lampholder. With the (SPST) switch–which he had tested--in the ON position, there was no voltage between the two wires. With it in the OFF position, there was ~120 volts between them. We tussled over this one for a while, coming to the tentative conclusion that Richard Panizari was right, there was something else on the circuit that was fed through the lampholder leads, at least a buried junction box. (David suspected that the other load included a ground fault.)
Johnny pointed out that David had left without solving the puzzle. When David left the job, he agreed with Johnny, he too was far from satisfied with the wiring. He had to warn the homeowner that while there was a very good chance that the chandelier had ben responsible for the burning smell, it was not certain. The wiring was old and iffy, and if she wanted to feel really safe it needed to be replaced. If smell returned and he had to return to investigate further, despite having a circuit tracer and a fiberoptic viewer he expected that he would have to open the walls.
After we used up what this troubleshooting puzzle offered, Rich brought up the problems he’s seen with poor wiring practices resulting in AFCI trips. Hammering staples on to Romex to hard could do it, he said. What he’d found when troubleshooting other installers’ work is that when they didn’t bother removing unused cable clamps, installers would nick conductor insulation by pinning them against the clamps when shoving receptacles into the boxes. Unfortunately, even when he’d correct these instances, the AFCIs still would nuisance-trip–sometimes weeks after he’d left. He’d use various tricks, for instance isolate portions of the circuits, but still not find the answers.
Ultimately, it seems to him, the only way to get circuits to work reliably with AFCI protection is to have them installed by careful professionals. Johnny has had the same experience. AFCIs work fine for him, but troubleshooting less-qualified workers’ AFCI installations can be baffling.
We adjourned about 7 PM, having spent close to an hour on discussion of Code and installation issues related to inspection and troubleshooting–not a bad substitute for a normal educational program.
In the next picture, you see Rich drawing his idea of what might account for the readings David got in the century-old house, while Johnny looks on.
This is the report of the George Washington Chapter, IAEI meeting on November 18, 2013. We were ten: four Associate members, three Inspector members, and two visitors, plus our speaker.
As usual, we enjoyed the generous hospitality of Ken Cain, Vice President of Capital-Tristate Lighting and Supply in Upper Marlboro/Forestville, MD.
As promised, out of respect for our speaker, we called the meeting to order promptly at 5:30 PM.
First we had a quick run through of chapter matters plus other news and information. Secretary-treasurer David Shapiro gave the Treasurer’s report: we continue solvent, thanks to the International Office’s Dues Disbursement. Membership Officer Karl Mirpanah had no news for us. Both reports were accepted without demur.
David then passed around a number of items in his role as Secretary. From IAEI’s Eastern Section meeting he brought UL’s statistical report of types of nonconformity their inspectors found all around the country throughout 2012 and into 2013, “Field Evaluation Deficiency Statistics.” Requiring that unlabeled equipment have a field inspection definitely can make a difference. From the American Council on Electrical Safety he brought a multi-page, specifically detailed report from OSHA, “Draft Update to the NRTL Program Directive,” of their new plan to supervise Nationally Recognized Testing Laboratories and make sure they are equipped and prepared to base equipment listing on adequate testing.
There were a few invitations as well. From IEC Chesapeake he brought an offer of IEC member pricing for any of our members who want to attend a December 10, 2013 training program in Laurel with the estimable John Wiles, a 2014 update on “Photovoltaic systems and the NEC.”At the behest of Chapter President Robert Welborne, David shared a photographically illustrated sheet from the Southern Maryland Electric Cooperative adjuring one and all to maintain clearances from and preserve access to their meters. This one elicited agreement, along with some amused comments.
The last item he circulated is a one-page description of the Coalition for Current Safety Codes. It encourages jurisdictions to adopt the latest version of each safety code when it is released. This is in contradistinction to, for example, the movement to adopt the NEC on a six-year cycle. David is about to join the group. He asked for, and freely received, the chapter’s permission to enlist in the Coalition as George Washington chapter member. Other chapter members are equally welcome to join the Coalition and attend their meetings: <firstname.lastname@example.org >. The next meeting is December 19 in downtown DC.
The Secretary’s report was accepted without a whiff of challenge. We then went around with very quick personal introductions, and were able to start the program right on time at 6 PM and went nonstop till a good bit after 8:30 PM. Our speaker was stalwart, and so were the majority of attendees. Some came for his presentation, like former chapter president Wayne Robinson, hadn’t been to our chapter meeting in a year or more.
We were very fortunate to be able to host Michael Johnston as the evening’s speaker. Mike is Chair of the NEC Technical Correlating Committee, NECA Executive Director for Codes and Safety, former codes and standards director for IAEI, and a charming speaker. He had agreed to spend some time on interesting 2014 NEC changes, and some on our questions. My word but we got going on the updates, with questions and comments and dialogue. Interspersed among the explanations of rule changes, Mike shared with us some of the process, the changing process, of the work of the Code-Making Panels. I have to admit being engrossed enough that my note-taking was somewhat sporadic.
We started with a good bit of focus on Article 100. Switchgear has been renamed with “Metal-Enclosed” removed, and “Switchgear” has been added to Article 408, heretofore “Switchboards and Panelboards.” Every recent cycle, Mike pointed out, has changed a definition–bathroom, kitchen, now Premises Wiring-System. In this case, the only change is an Informational Note (in parts of George Washington Chapter territory, Informational Notes are still FPNs). Another quick mention was a new definition, Retrofit Kit. His example is a kit listed–not Classified for compatibility with an individual product or products but Listed–for converting a linear fluorescent to an LED luminaire.
Moving on to Article 110, he talked very briefly about field-applied warning labels and about equipment disconnects equipped permanently for the use of field-applied locks.
As we continued with the details of individual Code changes, not all of them based on injury statistics, David asked, “What happened to body counts as the basis for accepting proposals?” Mike explained that reader-friendliness and reducing confusion are now recognized as valid reasons to tweak the Code. These are important enough for a Usability Task Force to have been in place for several Code cycles. Currently, the chair of that task force is the alternate to Mike as Chair of the NEC Technical Correlating Committee.
The 2017 cycle will follow a considerably modified change procedure. We have become used to seeing proposals sent in with substantiation by members of the public, and accepted or rejected. Some also are initiated by Code-Making Panels, and very possibly most are “Accepted in Principle”, “. . .in Part,” or “. . . in Principle in Part” by the panels. We then see the panels’ responses to our comments, including dissenting opinions. The result of this process becomes the next edition of the NEC, subject to confirmation–and occasional modification--at the NFPA’s annual meeting.
Henceforth, the ideas that we send in, the public input, will stay behind the scene, as raw material from which the panels themselves will propose all changes. The latter is all the Technical Correlating Committee will see. We did not go into how the substantiations will be presented or whether we will be shown dissenting panel members’ votes and views. (Instead of a Report On Proposals, the next document published will be called the First Draft.)
I’ll use this point in the meeting report to give you a useful link I learned about at the Eastern Section meeting: if you’re interested in submitting material for the 2017 Code, or tracking its development, go to www.nfpa.org/70next .
At about this point, the discussion went to roof raceways, and the generalization of rules about derating conductors in round raceways to all raceways. Wayne brought up the suggestion (perhaps sardonically), “Why not just require XHHW-2 on roofs. . .?” Mike told him and us to stay tuned for the next Code cycle.
Mike’s a pleasant story-teller. We drifted over at this point to the issue of when oh when the 2014 NEC will be adopted locally–or universally throughout Maryland. Michael talked about a call received from West Virginia as he was preparing to take on 2005 Code Change material for IAEI. His team had just finished with the 2002. West Virginia wanted IAEI to send him out to present a workshop on the 1993 NEC. Fortunately, IAEI had just transitioned from 35 mm to PowerPoint when they prepared the 1993 illustrations, so he was equipped with a visual aid.
Getting back to the 2014, Michael noted that, where flexible metal conduit or flexible liquidtight metal conduit is required for flexibility, there are fittings that are listed for support where used appropriately.
Continuing with the inside view, we learned that the DC Task Group is preparing an article addressing micro-grids–DC or AC. This may appear in the 2017. Surge protection will be required.
Now we moved on to portable generators. If a generator takes a 120/240 V locking plug, when such a plug is attached the generator must automatically disable any 120 V receptacles on the generator that are not GFCI-protected. The 120/240 V plug is used to serve the whole house, so to speak, and it is bonded to the frame. So far as those present know, Generac equipment does not offer any designs that do not bond both neutral and ground to frame.
And so to pools. The first thing we learned is that neither Wayne nor Michael likes the idea that one wire can be used as the bonding grid around a pool deck. Next, he mentioned that the reason we use an insulated green grounding conductor is to limit its corrosion.
So far, we’ve learned of the Usability Task Force and the DC Task Group. There’s also a New Technology Task Group. Its first co-chair happens to be the UL representative. And there’s likely to be a Task Group concerned with residential boat docks. Stray voltage is a concern, and there’s no rule presently addressing residential docks.
Moving along to proposals that did not make it, a change to the 210.52(A)(1) requirement regarding dwelling unit receptacle outlet spacing came surprisingly close to acceptance. It would have shrunken the maximum wall distance to any receptacle down to three feet!
Rick Panizari brought up the final item of the evening. NEC 225-39 concerns the rating of a dwelling disconnect. What if a building contains minimal efficiency apartments, not served by separate meters, but with their own panelboards? What’s the minimum size for the feeder breakers? Michael responded that you need to calculate the load.
Michael went two-and-a half hours plus. He would have kept going longer for us, but our very patient host Ken Cain came in at this point and explained that the cleaning crew needed to get in!
It was quite an evening.
Report of the September 17, 2013 meeting of the George Washington Chapter, IAEI.
Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply, we met in their training facility at 8511 Pepco Place, Upper Marlboro, MD. This is just off Branch Ave/ Forestville Road, immediately outside 495, the Washington Beltway.
David then mentioned a request on behalf of the Section for promotional gifts to be used roughly as door prizes. No one responded.
Finally, he asked a number of questions regarding residential concealment inspection. Suppose a built-in bookcase will be occupying an entire wall. There is no interest in floor receptacles, so the installer wants to bring a cable or raceway forward through the bookcase in order to mount receptacles at the front of shelves. What should be in place for close-in inspection? We agreed, at least, that the bookcase itself–the portion of the permanent structure that will be used for mounting--should not be installed until concealment has been approved.
Another question concerned wiring mounted on the inside of exterior masonry walls. Where rigid insulation will be installed over the wiring, and then the device boxes over the insulation, should the insulation be in place for rough-in, so that the boxes can be examined here they will be mounted, or should the insulation be installed afterwards, so that the cables can be fully examined at rough-in? Johnny Hoff noted that he’s been required to install plywood between outside masonry walls and metallic wiring methods. The consensus was that, in general, insulation should not be installed until after close-in is approved.One final question concerned the appropriate response to callers seeking referral to a Third-Party Inspector. Chapter President Robert Welborne suggested that David bring this policy question to the Section. He will ask the Eastern Section Executive Board for their thoughts. David did so, and the Section Board advice is that we tell anyone requesting referrals where to obtain lists of qualified providers that are maintained by the applicable Authoriy Having Jurisdiction.
We had two inspector members and five associates.PROGRAM
Robert Welborne, electrical plan reviewer for Prince George’s County, MD, chapter president, and electrical instructor at Prince George’s County Community College, walked us through information and calculations we rarely touch. Robert took over at about 6 PM. Supported by Charles Johnson, he explained some important changes in he expects to see in Maryland licensing and administrative law. While cities and counties will continue to issue electrical permits and perform electrical inspections, licensing and Code adoption will be in the hands of the state. This means no local amendments! Master and journeyman electricians will be required to assert that they have completed 10 hours of continuing education each time they renew their licenses, and five of these hours must be in-classroom hours, as opposed to online or televised instruction. These claims will be spot-checked. Individuals and organizations offering this instruction must apply for approval and be state-certified. (Robert has arranged for IAEI and our chapter to be recognized as providers.) Cities and counties that have electrical boards will still be responsible for initiating disciplinary action against licensees accused of improper behavior, but the boards’ findings will be forwarded to the state for action. Licenses will be required of master electricians, journeymen, apprentices, and possibly even helpers. Another item still on the table but not concluded is whether limited masters will be allowed to continue, or whether they will be required to earn full masters licensure. Finally, and perhaps in some cases problematically, they re considering a requirement that all electrical inspectors hold Master Electrician licenses. Any number of local facilities have their own substations. Members noted National Harbor, Johns Hopkins and USDA as some familiar names. Prince George’s College does not, but they do own all the high voltage equipment–13.2 kV transformers, switchgear and more. This is not the place to work up the equations and calculations that were delivered at a fearsome pace, but here’s a taste of what Robert covered. He started by defining complex power, or apparent power, as real power plus reactive (or imaginary) power. He defined the three types of faults, and the sequences, phase relationships between voltage and current, associated with them. From this he moved to the problem of a generator feeding one inductive motor and one synchronous, with different power factors. One was leading, the other lagging. What was the resultant power factor, and what size capacitor was needed to bring the new power factor up to spec? After this, he went over installation of a capacitor on the line side by the utility. This capacitor could have a much smaller rating. Finally, in response to a request, he calculated the load that would be observed at your facility’s transformer as the effect of a fault 20 miles up the line. What kind of ampacity would be needed as the result of this, at the transmission voltage?
At the end of the meeting, we invited Kenny Green, a relative new member, to introduce himself. He made it despite having been notified of the meeting only by a telephone message David left him the night before.
We adjourned about 8 PM, having spent the better part of two hours on the educational program.
Report of the May 21, 2013 meeting of the George Washington Chapter, IAEI. In addition to our presenter, three inspector members and two associate members attended, plus four guests.
Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital-Tristate Electric Supply, we met in their training facility at 8511 Pepco Place, Upper Marlboro, MD. Our immediate host was Ken’s assistant, Jackie Hart. She helped our presenter sort out the projection system.
To accommodate our presenter’s travel schedule, we postponed our business meeting till after the presentation.
Steve Rood of Pass & Seymour/Legrand flew in from Syracuse, N.Y. to talk to us about wiring devices and their protection. Steve described and showed us what’s changed and what will be changing, in 2008–and further back, in 2011, and what we can anticipate in the 2014.Steve has been in charge of marketing for the P&S commercial/industrial product lines, but is in the process of shifting to take over as their Codes and Standards expert because their long-term specialist is retiring at the end of 2013. He talked about code changes and he talked about related issues. This report will focus on the latter. We see abundant written material on code changes, so why repeat it?
Catalogs? But this is a hands-on group! No worries: Steve also brought us assorted devices for members to examine, including a combination 120 volt AC/5 volt DC(USB) device, a combination receptacle-surge protective device that buzzes when tripped. It provides common mode noise attenuation from 500 KHz to 30 MHz up to 20 dB. GFCI that also sounds an alarm when tripped sounds especially useful for protecting equipment that should not be left unpowered for a significant length of time but is located in an environment that calls for GFCI protection. How loud? A smoke alarm shrieks a minimum of 75 decibels; these GFCis run about 60 decibels at a similar distance. There were more.Steve graciously left the equipment for members to adopt. He also handed out code-change booklets. Robert took home a box of hospital-grade devices that may prove useful in the classes he teaches at the community college.
President Robert Welborne and Membership officer Karl Mirpanah had nothing new to report. Secretary-treasurer David Shapiro reported that our financial picture has not changed. Education Officer Shirley Clay did not attend the meeting or send in a report. All reports were accepted without demur.
There was one other activity. All who knew the Panizaris had the opportunity to sign a condolence card acknowledging the death of Joe’s and Rich’s father. We were sad also to learn, as we were circulating the card, that Ingram Munn’s wife died on April 29.
For our next meeting, September 17, we can anticipate a good brain workout. Robert Welborne is going to take us number-crunching, unless our Shirley offers a different presenter.
Our final meeting this year, November 19, will be honored by Michael Johnston, former director of Codes and Standards for IAEI, who now fills a similar position for NECA.
“Common Neutrals” was the advertised program theme. Seven members attended, plus one guest. We started shortly after 5:30, with officers’ reports.
Education Officer Shirley Clay distributed invitations to attend a $30, eight-hour seminar on PV inspection. It’s focused on, but not limited to, Code officials. The host is IEC Chesapeake, and the instructors are from North Carolina State University, She mentioned that she has scheduled a speaker for our November meeting, and needs suggestions for our May and September programs. President Robert Welborne and Membership officer Karl Mirpanah had nothing new to report. Secretary-treasurer David Shapiro reported our level of assets and commented that we have not yet received our bookkeeper’s report and invoice. Also, the International Office offered to sell us various 2014 Code books at a bulk discount. (There was no interest in this.) Finally, as Section Representative, he mentioned that the Eastern Section Board passed our proposed Bylaws changes on up to the International Office. Our next meeting is scheduled for May 21. There being no new business, after introductions we began our program. In this we were helped immeasurably by our host, Capital/Tristate’s Marketing VP Ken Giles. He provided the use of a laptop whose ports are compatible with their projector cable!
The program revolved around a series of pictures showing two large, down-facing junction boxes located beneath a residential basement ceiling; the panelboards feeding them; and NEC documents. NFPA’s Dennis Berry kindly blessed our Fair Use of their material.
The core issue is that even when we know in our stomachs that a practice is illegal, even when there is collateral evidence that the NEC does not intend for the practice to be allowed, the practice remains permissible. Only when specific wording is added to the NEC forbidding the approach does it warrant rejection. This is the case with common neutrals. As we saw in the slide show, in the 2010 Report on Proposals Don Ganiere identified the need to add wording. His proposal led to Section 200.4 in the 2011 NEC. Until a jurisdiction adopts a Code version incorporating this change, or the equivalent in a local amendment, installations using common neutrals have been Code-compliant. This presumes, naturally, that there are no other violations such as circuit mislabeling. There was no objection to Ganiere’s clear explanation of the need for this addition to the article by the members of the Code-Making Panel. The Report on Comments added a supportive comment by Mike Holt, and, again, no objections.
As Andy Cartal pointed out in a pre-meeting telephone consultation, Section 215.4 explicitly permits the limited use of common neutrals for feeders, and Section 225.7 explicitly permits the use of common neutrals in outdoor lighting, Despite the presence of these permissions, without the explicit language in the 2011 Code forbidding common neutrals elsewhere, these sections actually served to limit the use of common neutrals in feeders and outdoor wiring. What this means in practical terms is that the installation David showed in the slides, which is in a local jurisdiction that has not yet adopted the 2011 NEC can pass. Yes, it includes branch circuits using common neutrals, but the installer sizes the neutral/s so as to carry the maximum return current than may be imposed.
That’s it in a nutshell. Because chapter meetings have room for variety, this didn’t end the matter. To Rick Panizari, any sharing of a return conductor by multiple energized conductors looks like a multiwire circuit. If it doesn’t fit the definition of a multiwire circuit, this just makes it an illegal multiwire circuit. Yet this argument is absent in the ROC and ROP. No one raised this objection as part of the Code-making process.
To Karl Mirpanah, all this misses the point that the installation was a bad design. If you have a long run to a variety of outlets, you don’t mess around with individual low-ampacity branch circuits, you install a subpanel closer to the point of use. Having visited the job pictured, Karl mentioned that the homeowner, not an electrician, was responsible for all that I’d seen. He also explained the reason for the common neutrals. He believed the owner had installed the junction boxes because he had cut back pre-existing branch circuits’ MC cables, and they no longer reached the panelboards.
At this point, our discussion departed from the slide show, from the issue of common neutrals and even from the need to enforce the NEC as written and change it when it doesn’t say what it should. David mentioned the fact that, so far as he can tell, even in the 2011 NEC, there’s no requirement for handle ties where common neutrals are allowed and commonly found, namely in festoon lighting. This led to a story or two about interrupting energized return conductors. Ingram Munn chimed in here, as did Shirley Clay with stories about dangerous, illegal installations where she’s been called in. In one case, she could see the dark evidence of three small fires the building had already suffered. Rick mentioned a disagreement he had with someone who was guided by the International Residential Code (IRC). He expressed concern over apparent differences between its electrical provisions and the NEC. David offered to look this up, but unfortunately the person Rick’s dealing with relied on a rather earlier version of the IRC than David has. Karl noted that electrical Third Party Inspectors in DC now have to pass a test on the ICC’s International Energy Conservation Code. He mentioned that Loudon County, VA has had a motion detector requirement for commercial spaces for 10 years. An office space will have a motion detector (with an override) installed to control lighting, and pass inspection. Then someone will be still enough to trigger shutdown, and they’ll get the detector replaced with a simple switch. He also mentioned (with a little hyperbole) that homeowners can use postcard permits in D.C. to perform any electrical work other than service upgrades.
Having finished our discussion of common neutrals, we had a few slides left. They were a reserve, included in the PowerPoint(R)-type show against the possibility that we would have time to spare. We had some fun tsk-tsking other problems with this installation, problems that were emphatically evident on the remaining slides. Karl, Rick, and I believe Robert’s guest Chris Shiaris were expressed their disgust with utility (handi-) boxes. One thing is clear: if Karl is called back and asked to inspect the work in the basement panelboards and junction boxes, he’s had plenty of advice on what to look for.
We adjourned a few minutes before 8 PM, having spent about two hours on the program.
This is the record of our meeting Tuesday, January 15, 2013.
Two members were present at the announced 5:30 PM start time. Over the next hour or so, further arrivals built attendance up to three Inspector members, three Associate members, and one nonmember. We were quite concerned about the non-appearance of one of the evening’s scheduled presenters, who had planned to arrive at 5 PM to set up the PowerPoint show he had put in long hours developing. Due to his absence, we modified the program.
Karl Mirpanah, P.E., our Membership officer, led us into a discussion of lightning protection and NEC requirements. The risks from lightning strikes lead him to believe that where service comes to one building, which sends a feeder to a second building, you should keep the second building’s grounding system separated from the first building. Otherwise, a strike at Building 2 could result in considerable damage at Building 1. Moreover, we learned perhaps an hour in to the discussion, he does not believe in bonding a building’s grounding electrode system to its lightning protection array’s grounding electrode system.
If he goes on a job and sees the likelihood that a lighting protection system could let a strike cross into the structure’s service equipment, he wants an interrupter installed ahead of the equipment. He received his engineering education in Europe. There, he noted, a main breaker is designed not only to protect against short circuits and overloads but also to detect ground faults and interrupt power to them. However, in those electrical systems a lightning protective fuse is installed ahead of the main breaker.
Everybody got into the act. President Robert Welborne quoted the code Section, 250.106. Rick Panizari suggested that even without a lightning protection array, a building’s grounding electrode system offers some protection. Karl challenged this, saying it would burn right up due to the huge power in a lightning strike. Secretary-treasurer David Shapiro suggested that the main purpose both of installing a building’s normal grounding electrode system and of bonding it to a building’s lightning protection system probably is to minimize differences in touch potential under normal circumstances.
Shirley Clay, who recently rejoined IAEI, agrees that the two grounding electrode systems need to be bonded together. She rose to the occasion and sketched on the whiteboard her idea of where and how they need to be bonded. Her opinion is that they should be bonded with conductors the size of the electrical system’s grounding electrode conductors. This is one of the comments that brought us to the question of sizing lighting array and lightning down conductors. David’s understanding has been that the down conductors need to be a minimum of 10 AWG. Karl talked of the half-inch, probably aluminum rod used both to form the array and to serve as the down conductors in the National Harbor system he has seen. Rick asked how the sections of rod are connected, and Karl suggested welding. How was the rod run? With no bend angle greater than 45 degrees.
This returned David to the argument that there would be no danger from bonding the two grounding electrode systems, using a sharply angled bonding conductor that came back up from the lighting system after the point at which it reached its own electrode–run, in other words, the very opposite of the smooth way lightning down conductors should go. David noted that the intersystem bonding termination required by Section 250.94 seems to be intended for purposes such as bonding to the lightning protection array’s electrode system.
Karl seemed to agree that it would be safe to bond the two systems, if they were bonded right at the ground ring which is his lightning array grounding electrode of choice. (Karl also believes in running a separate down conductor from the lightning array at each corner of the building.)
Shortly after 6:30–having waited till then for the arrival of any members who had forgotten or overlooked our change in starting times--we broke for business. First, the minutes of our previous meeting were accepted unanimously. We dispensed with committee reports to focus on annual meeting tasks.
David explained that, as we lacked a quorum by one Inspector Member, the Inspector Members present could accept Robert’s proposed candidates for this year’s officers, but David would have to send out a mail/email ballot to the full Inspector membership before the nominations could be officially, formally, confirmed.
Robert nominated himself to continue as President, David to continue as Secretary-treasurer and representative to the Eastern Section, and Karl to continue as Membership chair.
This left one critical post vacant: Education. Robert explained the duties of our Education officer, and David elaborated on them. Shirley volunteered to take this on, was gladly accepted by Robert as fill-in appointee, and was unanimously accepted as candidate. There were no volunteers for other positions such as Vice President, Nominating Committee, Auditing Committee, or Budget Committee.
We spent some time discussing possible presenters and topics for future meetings before returning to the evening’s Code talk.
We returned to last month’s discussion of firehouses. Rick said he still can’t see calling firehouse spaces residential.
Rick: A sleeping area, sure, but even so why would you use Tamper Resistant receptacles in firehouse sleeping area? There’s no reason for children to stay there.
Daryl Stevens (an Inspector Member whose presence was thanks to Karl’s encouragement): “How do you design multiple use occupancies?”
Rick: “A bunk room is not like a residence where you move furniture around.”
Shirley “Is the ‘apartment’ standalone?”
Rick: “Well, there are bunk rooms, private rooms, common showers, . .”
Robert: “Under 210.60 there are at least two receptacles on separate circuits in the kitchen.”
Daryl: “Some firehouses are like small assembly occupancies; nowadays they are not used as gathering places.”
Robert: “Nowadays is it commercial?”
Daryl: “What is the occupancy limit?”< BR> Rick: “I’d treat it as commercial. And I could see it as requiring arc-fault protection”
Daryl: “Calling it commercial gives much more latitude for design.”
Robert: “The plan [that started this discussion] started as commercial, but it was kicked back a couple of times.”
Karl: “You can’t call it residential, because it’s not family-occupied.”
Robert “I would size the service for commercial. And straight commercial including the bunk rooms. Though it does have multiple occupancies.”
Daryl: The Takoma Park firehouse has a basketball court in the basement.”
Shirley: The Landover Road firehouse was small, but opened up the biggest room to be used for neighborhood parties.”
David speculated that there might be an NFPA standard specifically addressing firehouses, and for a while Shirley looked for one, using her smart phone. This did not yield any epiphany. Robert promised to check on this Wednesday morning.
Visiting non-member Monica Cortez, P.E. showed up at this point, and we put her on the spot–we asked her opinion about the bonding of service grounding and lightning array grounding. She agreed with the NEC model: install two grounding electrode systems, but tie them together.
In a last comment on Karl’s concerns about lightning protection, Rick commented that he has a surge arrestor at his meter can, hence upstream of his service equipment.
This brought us to 7:30 pm, when Robert gave his presentation.
Robert finds few people know how to size protective equipment based on transformer impedance. Lacking evidence to the contrary, he starts out by assuming transformer impedance of 5.75%. Using this assumption, he offered a first example:
At 1000kVA a transformer’s primary is fed 4160vV, and it’s stepped down to 480V at its secondary windings. Dividing incoming kVA by voltage, and by 1.73 because the power is carried by three phase conductors, yields 139 Amps coming in through the primary. Table 450.3A covers maximum setting of overcurrent protection for transformers over 600 V, but to keep the calculations simple he sized everything at 100%
Multiply 139 amps by the ratio of primary to secondary (4160/480, which is 8 2/3) and we get 1203 Amps available on the secondary side. We start with 5.75% times 480V to get 27.6 V and because volts=is amps times impedance and thus impedance=volts over amps, 27.6V/1203A=.02294 ohms. Where we assume a secondary no-impedance short circuit or bolted short, that’s the only impedance, we divide the secondary voltage by that, 480/.02294 to get maximum possible secondary current of 20,924 A. This means we need protection at the 22kAIC level.
However, many manufacturers are selling 2-3% impedance transformers, which require higher AIC protection.
As a rule of thumb, Robert commented, with 30 kVA transformers, 10kAIC equipment is fine.
His second example used a 500 kVA transformer, 4160V primary, 208V secondary and 5.75% impedance. He calculated a possible secondary current of 20921.8 amp here. However, with a 3% transformer impedance it would be 46,300 A.
Rick mentioned a shortcut; Daryl grinned and said it has been many years since he had to calculate AIC by hand.
As we wound down for the evening, Robert mentioned the CE courses he is offering through local community colleges.
A number of people commented on their use of a patent clamp used to bond grounding conductors to enclosures. Nobody believes that their use is required, but most of those present liked them One senior member actively dislikes them.
We adjourned around 8:15.
The next morning, Robert reported some answers, based on the 2003 Life Safety Code and the 2009 International Building Code. A fire station’s bunkroom is to be treated as a multiple occupancy building. He gathered some of this information and mailed it to David. It will live with the chapter’s NEIS collection.
He added, “ If the Life Safety Code classifies it as a "Dormitory", then Article 210.60 would apply which also puts us back at Article 210.52. Just to clarify.”
Robert also mentioned that he and our visitor Monica Cortez have worked on several designs. One involved a transformer serving a water treatment plant. The incoming voltage was 13.2 kV, capacity was 2MVA, secondary voltage 480, which was fed throughout the plant. The manufacturer supplied its impedance, 7.4%, and they had to figure out the AIC. They also faced a challenge keeping the 13.2 kva conductors to a maximum of three 90 degree bends (the utility spec, more severe than the NEC’s restriction) before terminating into switchgear.
This is a report of the George Washington Chapter, IAEI’s November 20, 2012 meeting.
We had three Inspector Members, four Associate Members, and three nonmembers, one of whom was our co-presenter, Ray Adkins, P.E. The meeting was called to order and our presentation begun at about 5:45 and finished around 7:20. After this we took care of business.
Before we got under way with the planned presentation, Rich Panizari showed us a handful of THWN conductors some of which had melted in conduit as the result of a fault hundreds of feet away. Only the insulation on the conductors associated with the faulted circuit had melted together; the others that had shared the same underground conduit showed no damage.
After discussing this phenomenon, we moved on to the featured presentation. The installation that led to the conflict between engineering judgment and NEC requirements came to be designed because of a series of fires at two apartment buildings. The local inspection authority insisted that the owner bring more power to the buildings if he wanted to continue renting apartments in them.
The upgrade consisted of a service brought to one building and a feeder from this to the second. Both were plain masonry buildings, with no building steel. The P.E. designer, Ray, did not like the idea of running a grounding conductor back to the first building. It turned out that his main concern was with the likely result of a lightning strike to the second building. He would have preferred to give it just a simple path to ground at the second building.
Ray had brought along blueprints, as prepared by the architect, and was able to trace the circuiting and paths he was describing. With a larger group we would have needed to use the projector and PowerPoint or equivalent slides. Here we managed to gather around his part of the table, some of us craning our heads a wee bit.
The snarl that we gradually untangled is that Ray looked at bonding and grounding as ensuring a path to earth; as the rest of us made clear, we look at it as ensuring a relatively low-impedance path for faults in the electrical system to complete their circuits to points of origin so as to trip their overcurrent devices. Ray understands quite clearly that lightning is unlikely to trip overcurrent devices. However, he was concerned about possible risk to people at the first building from lightning strikes at the second.
Chapter outreach officer Pete Bowers suggested an exotic possibility: Ray’s installer could run an isolated grounding conductor to the second building’s panelboard. This option did not interest Ray.
As Ray explained the details of his design, we learned that the feeder had been run underground in rigid metal conduit almost to the second building, with just the last few feet enclosed in PVC conduit. Chapter secretary-treasurer David Shapiro suggested that he bond the end of the metal conduit to the second building’s panelboard. In the course of the discussion, Pete had emphasized that it is quite common for knowledgeable people to insist on a separate grounding conductor, because they distrust the tightness of couplings, connectors and setscrews and don’t want the system to ultimately have a high-resistance ground.
Ray moved on to talk about the IEEE position that for protection against events such as nearby lightning strikes, two surge protectors should be used, one upstream and one further down. As we talked about the paths that lightning takes, Pete talked about the need for smooth turns in lightning arrays’ down conductors--and mimed shaping them.
After we were done with all the side issues raised by the topic of Code requirements for grounding and bonding–and grounding electrodes, and the need to join all available elements of a grounding electrode system, we moved on to the second presentation.
Ray’s second concern also was presented accompanied with an architect’s blueprint. It showed the planned upgrade of a firehouse. How should the space be categorized, in terms of load calculations, circuit supply to cooking and dining and bathroom areas, and receptacles? Should they treat it all as residential, partly as residential, or not at all?
Should any of it be treated as a place of assembly? In another firehouse, the large area their equipment normally occupies sometimes is cleared and used for fundraising dances. In the past, this fire company had not made such an assembly-type use of the space. Should this be considered?
The plans showed bunk rooms, a few private dorm rooms, bathrooms, a workout room, a commercial-type kitchen that was used to prepare food for fundraising events, more- and less- private bathrooms, a conference room in which the firefighters often hung out and watched television while waiting for fire calls, a watch room, . . .
If the building was not all residential, did it require a fire alarm system? If the building was all residential, GFCI receptacles were needed accessible to every bathroom sink. If all–or a particular area--was residential, load generally could be calculated at three watts per foot. On the other hand, receptacle spacing would be far touchier. Outside of dormitory and bunkroom areas, did the building need to be treated as residential in terms of egress requirements? In this instance, the architect and plan reviewer agreed the answer to this last question was no. The electrical inspector on this job wanted AFCI protection in the fitness room and the conference room. He also wanted Tamper-Resistant receptacles installed throughout this adults-only occupancy, and residential receptacle spacings only in the dormitory rooms.
We chewed this over, a good bit. The most important concern, we agreed with Ray, is to achieve some consistency between plan reviewers and inspectors in making these decisions.
Next came the question of wiring method. The job was specced for MC cable, but could NM be used? Pete raised the question of building height, but a number of others pointed out that the NEC has dropped this criterion, substituting building type, as described in (2011) NEC Annex E. Subsequent to our meeting, Pete looked at information in the (2003) International Building Code, and found neither anything to contradict Annex E guidance nor anything that would help us classify firehouses or areas within them. The IBC essentially refers the user to the NEC for guidance on electrical design.
After we had our fun with this challenge, chapter president Robert Welborne raised the question of whether a sprinkler system’s jockey (pressure-maintenance) pump can and perhaps should be fed from the same circuit as the fire pump. Ed Bihlear noted that if the jockey pump is fed from a non-emergency panel that is generally accessible, it can accidentally lose power all too easily. When this is the case, the pressure drops only so far before the fire pump itself will come on. This means all the whistles and bells go off, with the fire department alerted. Therefore, it is far better to feed the jockey pump from an emergency panel. Here’s a case where NEC Article 695 is more permissive than NFPA 20. In fact, the jockey pump can be fed off the fire pump controller.
Ray brought up the tap rule. Ed mentioned a job on which the fire pump kept being activated and he kept being asked to adjust the overcurrent device’s trip setting till finally he balked and looked for himself, finding a defective solenoid.
After this we thanked Ray and let him go. His wife, who is also his business partner, had been waiting outside all this time! (She did have her smart phone for company.)
At about 7:20 Chapter president Robert Welborne convened our business meeting and turned the floor over to David, who was briefed in September on the procedures that are particularly important to those who oversee us. Although we were shy of a quorum, as usually is the case, we proceeded as though we were in a position to transact business.
David started out by announcing that IAEI’s server is down at present, and then brought up the question of our chapter’s minutes. The minutes on our web site were unanimously accepted.
Then, Robert, representing our education committee, gave his report. A number of members expressed interest in another field trip, to visit a generating facility that uses gas primarily rather than coal. Robert looks forward to consulting with Harry to plan future programs. This report too was unanimously accepted.
Next, Pete, our outreach officer, was asked to discuss relations with other groups. He mentioned that the forthcoming Maryland Uniform Electrical Licensing Exam Committee meeting would be open to all. It takes place on the evening of November 28, at Capital Tristate - White Marsh, 8009 Corporate Drive, White Marsh, MD.
After this, he shared some thoughts about problems with Washington, D.C.’s Third Party Inspection (TPI) system. He mentioned difficulties in the areas of record-keeping, of supervision by a Person In Charge (PIC) registered as a P.E., and of the interface with DC inspectors. Pete got agreement on one aspect from Karl Mirpanah, another TPI, and from David, who had resigned as a TPI out of discomfort with the PIC format.
Pete’s report was unanimously accepted.
Our membership report was next. Karl Mirpanah had no news; Robert mentioned having talked about the organization to ten people. This report too was accepted unanimously.
Finally, David offered the Treasurer’s report. Because we lack both a Budget committee and an Audit committee, he detailed our financial income and expenses for the year. He particularly brought to the meeting’s attention the generosity of Pam Panizai, our bookkeeper.
Next, he detailed the costs associated with sending a chapter representative to the Eastern Section meeting. We have traditionally sent the secretary-treasurer as our representative, covering all expenses. This goes back to the days when we were offering seminars that brought in extra income. The short version of all this is that we’re broke. Because we’re a relatively small chapter and engage in no income-producing activities, we rely totally on the twice-yearly dues distribution. It’s not enough to cover annual meeting expenses, certainly not when the meeting is on Rhode Island.
David’s report, including his suggested plan for expenditure of what we have--reimburse what we can, but leave $100 in the kitty--was unanimously accepted.
We visited Genon’s Chalk Point generating plant on October 9, 2012. (Genon may be owned by NRG Energy, Inc. by the time you read this.) We kept this field trip informal rather than treating it as a normal meeting. This was largely out of consideration for our host, who’d had a long day. In addition to this concern, not only didn’t we have a quorum, our roster included as many guests as members. We had two Inspector Members, two Associate Members, and four guests, all Professional Engineers.
Genon had security procedures in place. First off, our ID was checked against the list of visitors approved for the evening. As soon as we entered the gate, had to sign releases in which we took responsibility for our own safety. However, releases were not enough. We had been warned of the need to bring Personal Protective Equipment (PPE).
We all started out with hard hats and, one way or another, protection for our ears and eyes. The one engineer who had forgotten to bring safety glasses was given a pair–awfully nice of our host–and two or three accepted earplugs. Ed Bihlear was the only one of us who brought ear muffs, leftovers from his days with a Metro contractor.
As soon as we had convoyed into the parking lot, we were escorted into a classroom trailer where we enjoyed a briefing from Wayne Hale, Chalk Point’s trainer and our immediate host. His topics ranged from material sources to legal requirements to politics to chemistry to waste heat fish farming to supplying gypsum for drywall manufacture. We also heard his views about state versus federal pollution standards and about election year versus normal attitudes towards coal.
After the briefing, we spent over two hours on our guided tour through the awesome generating plant. The scale is immense. In explaining the critical need for backup power to assure bearing lubrication continues to be pumped in, Wayne commented that an order for a replacement 13.8 kV motor might result in a three year wait for delivery. Still, bigger is not always best. Toward the end of our visit, Wayne commented to Haddus Neway, an avid questioner, that they are reaching the inversion point where the economies of scale diminish. It may be more cost-effective to install two huge motors or fans rather than one single--colossal--unit.
As we toured the outside plant, the PPE seemed hardly necessary. On our way up to the control center, though, we walked past loud, dirty--let’s repeat “loud” once more--equipment such as a monster turbine. In this environment we appreciated our hearing protection. Amusingly, a few questions and comments continued to be offered during this stroll; this seemed like chatting with a dentist while his drill whirs and grinds inside your mouth. Giant generators roar.
One aspect of a generating plant that seemed particularly important for us to understand is the difference in rules that utility operations face. In accordance with NEC 90.2 (B) they are generally covered under the National Electrical Safety Code, the NESC, which the utility itself is responsible for enforcing, not the NEC. Sure, consumers have a lot to say about electricity prices, and reliability, and sometimes pollution. However, to have nobody looking over your shoulder telling you to keep to the rules as you run your job seems worlds different from the electrical work that we know.
We saw that it’s not quite so hard-and-fast. Soon after our briefing began, Robert Welborne pointed out that applications of NEC 90.2 (A)(4). Thanks to this, the wiring in buildings not used for generation, such as the classroom trailer we started in, or the storage buildings that we had walked past, remains under the NEC. The AHJ enforcing it remains the local AHJ. Later, when we were all ascending in an elevator inside the building that contains a huge turbine, coal conveyor, and so forth, Karl Mirpana pointed out the elevator certificate, enforced the same as it would in any other establishment. Our guide, Wayne, also sits on the plant’s OSHA committee, and safety committee, and ergonomics committee, and more. These help the utility address yet more requirements enforced by outside bodies.
A question remained: how does a facility ensure that it complies with the NESC? When Wayne brought us in to the operations center–we were warned again to touch NOTHING--we asked one of the white-shirted operators about NESC enforcement. He explained that before any change is made, the engineering department prepares a proposal. Our equivalent in NEC-land may be plans, or permit applications. At the generating plant, the proposal is sent upstairs for several levels of approval. Then when the work is performed, he said they send in-house inspectors to confirm its compliance. (One of our former chapter presidents, perhaps in a similar fashion, fills this last function for a government entity that functions as its own AHJ.)
Not long after our visit to the Star Trek-like control center, Wayne guided us back to the classroom trailer. He asked for final questions, we distributed CEU certificates to those owed them for attending previous meetings, and we reminded people of our next meeting. After this we headed home, keeping careful watch on the dark roads, as Wayne had warned us about deer and wild turkey.
Our new President, Robert Welborne, provided the educational presentation, describing mistakes frequently found in the plans accompanying permit applications. We had a lively discussion, with everyone engaged.
The first section Robert mentioned is 250.24(C)(1), requiring a neutral at each service disconnect under most conditions. Next, we spent a good bit of time going through examples of 250.122 applications. Plans with paralleled conductors have showed equipment grounding conductors in each raceway sized for just the conductors within each raceway. Also, where ungrounded conductor sizes have been increased, perhaps not because of required derating but to reduce the expense of wasted energy, designers have neglected to increase neutral sizes.
He commented that often the Professional Engineer (P.E.) who stamps the plans is a mechanical engineer. How is this legal? So long as the P.E. claims some knowledge of electrical topics, he is allowed to take responsibility for the design of electrical plans.
Karl Mirpana, our Membership Officer, mentioned that in Washington, D.C., the P.E. has to be an electrical engineer. Jim Wooten, our long-term President and presently our Past President and Vice President, said that it is quite common for a civil engineer to stamp plans in PG. (We were happy to see Jim looking a whole lot better than he had at our last meeting or two, and sounding livelier.)
Robert continued, mentioning that in his experience every designer or P.E. whom the plan reviewer has had to contact has accepted his correction civilly. This said, he has been challenged by companies that did not want to have to modify their plans. He has had as many as six people in the room, trying to change his determination. However, he showed his calculations, and the engineers and officials and lawyers could not show these calculations to be wrong, so he stood his ground, and the jurisdiction's chief of plan review stood by him. The engineers had to redesign the installation in order to receive their permit.
To save time, comments on plans are emailed nowadays, with backups kept on the county’s computer. Pete warned that the plan reviewer had better keep his own backup copies.
In answer to a question, the judicious plan reviewer mentioned that he checks not only the electrical plans but also whatever associated plans are submitted, to make sure there are no conflicts and no necessary items omitted from the electrical plans. This can add up to as much as 16 pages,
John Hoff asked Robert how long the reviewer spends reviewing a set of plans and checking over the calculations. The answer was, “As much as a day.” Johnny said it had sounded like it could take a week.
Johnny beefed about the amount of time PG’s permit process can take nowadays with Sparky having to get on the same lines and go through the same clerks as everyone else. Robert did mollify him somewhat by mentioning that the permit office now works through lunch.
For a while we discussed large projects a reviewer may review, such as amusement parks. Johnny wondered what kind of power a roller coaster draws. We learned that the answer can be 500 kVA–with the circuit protection upsized to 250% to allow for starting current.
The conversation roved widely. Pete Bowers commented on plans that left spare room for additional circuit breakers, but didn’t allow for any additional loads in sizing the panel feed.
Secretary-treasurer David Shapiro mentioned that he had just seen a Smart Meter at a DC residence. To his surprise, the meter cover was secured with a crimped-wire seal. This conflicted with what Steve Atkinson, P.E., manager of engineering for Pepco, told us a year ago: that Smart Meters would all use locking rings. No complaints here.
Various members talked about how they have dealt with the power company in performing service upgrades. Pete asked others what they do to follow up on completed heavy-ups. Do they check with the utility? The AHJ responsible for the cut-in notice? Pete said it has taken as long as three years for the utility to finish its part. He also said that one party to the process (I won’t get specific) lies. Johnny said he calls the customer to learn whether the changeover has been completed.
Now Robert went back to his presentation. Another frequent mistake, he said, is confusing Table 250.66, for system grounding, with 250.122, for equipment grounds. Inadequate panel schedules is another common error, we agreed. Article 518, Assembly Occupancies, is complicated by the factor noted in 518.2(B), that a mix of occupancies commonly found is in one structure. At least one reviewer notes on such plans that those portions to which Article 518 is applicable must comply with its rules.
The last item in the prepared presentation was the local adopting statute, PG Subtitle 9. The County is getting ready to adopt the 2011 NEC, and a revised version of Subtitle 9 is being reviewed for adoption. Items that will be covered in the 2011 NEC have been removed from Subtitle 9. An example of what is found in Subpart 9 is a requirement for not just lighting but emergency lighting at the electrical panels in commercial occupancies. Pete commented that this would be required elsewhere; apparently it was in Subtitle 9 to ensure that electricians unfamiliar with life safety rules would notice it.
With this, the presentation was done. Now Karl went up to the whiteboard to describe and draw a problem he had faced on a recent inspection. An installer wanted to use PVC as a service mast, extending a few feet above the building. Karl insisted that it be replaced with rigid or intermediate steel conduit, and the electrician asked him to point out this requirement in the NEC.
We shared many stories about the need for rigidity, but finally the resolution came down to the AHJ’s right to demand a mast satisfying him as “adequate,” in accordance with Section 230.28.
That was about it for (a non-exhaustive overview of) the technical portion of the meeting. We did handle one business item before leaving: our vote. While we did not quite achieve a quorum under present rules, ballots had been sent to all Inspector Members more than 20 days before the meeting, so between ballots that were returned by mail, and those filled out by the two Inspector Members at the meeting who had not returned them beforehand, we had a valid vote. Everything up for a vote passed. This includes our slate of officers, the proposed bylaws amendments, and Robert’s request for chapter support for his candidacy for IAEI’s manpower pool.
In other matters, our Programs Officer, Nigel Nesbeth, picked up a CEU certificate, and . . . no one went home with the monograph mentioned in the meeting announcement: American Society of Agricultural Engineers Paper No. 86-4529, “Electrical wiring methods and materials for swine housing.” Not surprising: no one had arrived wearing a Stetson, to improve his chances. (If you read the meeting notice, you might understand this. If not, don't worry about it.)
This is the report of the George Washington Chapter's business meeting the evening of March 20, 2012. Because of the critical importance of this evening's business, the ten attendees (five Inspector members and five Associate) came prepared to focus on the well-being of the chapter, without taking time out for an educational presentation.
Retiring president Jim Wooten started in informally around 6:30, with a full house. Returning member Johnny Hoff and Third-Party Inspector Tom Siewicki introduced themselves to Secretary David Shapiro. Tom was the lone member to return the SASE mailed out with the meeting notice, at the suggestion of Vice President Robert Welborne. (Tom's note, saying that he would make it to the meeting if he could, arrived in the chapter's mailbox the day after the meeting.) Loyal attendee Karl Mirpanah also avoided being late, despite having been stuck in traffic. (Karl's cell phone message saying he was running late but en route reached the David's sweetheart, David having already left.)
We learned that inspectors in the adjoining Delmarva chapter, whose meetings have been quite well attended, receive compensatory time for attending. In the early years of our chapter, this was true of inspectors working for Prince George's County, Maryland, who made up a good part of our membership. Still, the lack of CE requirements, and in fact for any credentialling, has not prevented 50-some inspectors and electricians from sticking with our chapter. <
The major question remains: how we can best serve the members who haven't been showing up regularly to enjoy our meetings and programs? Another question is how we can best serve the larger electrical community, especially the community of local inspectors, and ideally attract them to IAEI.
Many ideas were bruited by Harry Langway, Joey Panizari, and the rest of us, a goodly number being approaches that are used by other groups. They ranged from dinner meetings, general mailings to local members of the industry, media ads, flyers in supply houses and on-including preparation of a snazzier web site. Some of these are unrealistic, while others may be pursued.
Pete Bowers plans to talk to other organizations about possible synergies, as well as siccing one of his daughters on the appearance of our web presence. Jim selected him for service on the Board as temporary Outreach and Publicity Officer, to be confirmed in our forthcoming election. Karl, who was in the process of transferring his membership to our chapter, has clear ideas about challenging people to bring in member candidates. He himself plans to bring another five inspectors into the organization and to our meetings. Karl was selected as temporary Membership Officer, to be confirmed in our forthcoming election.
To round out the slate, Jim selected Robert Welborne to succeed himself temporarily as President and David as Secretary-Treasurer/Section representative, while Jim himself takes the position of Past President and Vice President, for as long as he is able to attend. (He was not looking well.) This is all subject to confirmation by the electorate All these appointments/nominations were confirmed unanimously by the inspectors present, as was the plan for David to submit the proposed revised Bylaws and Robert's application for the CMP candidate pool in the same mailing as the Board candidates.
No one present was selected as temporary program/ Education officer, or as Budget/Audit officer.(After the meeting, our provisional president selected Nigel Nesbeth as temporary and nominee Program/Education Officer.)
The other thing that happened at the meeting is that we shared war stories. Heads were shaken over the lack of commitment among so many in our industry who seem nothing more than time-servers. David tried to argue against the apparent blanket dismissal of ordinary inspectors, but his voice was mighty lonely.
Fortunately, grousing was not the focus of the evening. We got some work done!
We did hear one piece of very bad news: long-term member Ron Kimble is deathly ill, in even worse shape than Jim. David will send him a card on behalf of all of us.
Jim called the meeting to a close about 8:30.
In response to a question, Alex also told us about the possibilities he sees for NEMA in daylighting. One problem is that when, for example, big box stores install skylights–as they can be mandated to do–the quality of the light, during the brightest part of the day, may wash out lighting effects intended to bring products to customers’ attention. He is slowly bringing together a group interested in daylighting management, whether through mechanically controllable louvers or through installation of electrochromic glass, whose ability to transmit light can be reduced and restored electrically. At present, there are no standards to coordinate these technologies with dimming of electric light.
Daylighting management is certainly not the only area of electrical manufacturing that is not represented by a NEMA division. Solar energy is another, perhaps considered too much of a niche area for decades. Visiting E.E. Mike Wechsler brought us up-to-date on the economics of residential solar. He reported that in Washington, D.C., after rebates, a forthcoming single-family solar installation required maybe $6000 out-of-pocket investment. This means a payback period of merely a couple of years, followed by a couple of decades of sheer profit.
One last gripe was raised, concerning upgraded luminaires, such as solid-state-ballasted linear fluorescents that replace old magnetic-ballasted units. First, they sometimes seem to be short-lasting, an issue that Alex had addressed earlier (call the manufacturer’s complaint line!). Second, they can cause visual discomfort. Instead of talking about harsh color, glare, and changes in light level, people mentioned flicker as a possible cause. Alex commented on people’s variability in detecting flicker, with 100-120 Hz the usual limit of perception.
"Tell your problems to the people who made the equipment"
is not where Alex left us, even with respect to the earlier
complaints about incandescents. In the days following our meeting,
Alex consulted manufacturers' experts. To get full service out of
incandescent lamps and to avoid their premature failure, they have
three recommendations. The first two, at least, will be familiar to
One, make sure the lamps are not subjected to overvoltage. If necessary, install 130 volt or even 140V traffic-type lamps in luminaires on any nominal 120V circuits whose voltage reads high. (At our September 2008 meeting, Bill Poulin told us that utilities commonly serve the middle of a run at somewhat high voltage, so that anticipated voltage drop doesn’t bring it down too far by the time the cable reaches customers at the ends of the run.)
Two, make sure they are not subject to environmental stress such as vibration unless designed for the purpose, as are Rough Service lamps and oven lamps.
Three, to avoid disappointment with any sort of lighting, buy reputable brands. This does not necessarily mean lamps sold by the big three (Sylvania, Phillips, and G.E.), but at least buy lamps whose packaging indicates compliance with standards.
Our previous meeting took place on May 18, 2010. Reports indicate that Michael Johnston and his associate put on an excellent presentation regarding the NEIS program, for a very small house: four inspector members, two associate members, and one inspector nonmember. Both Jim Wooten and David Shapiro were unable to make it, for health reasons. Harry Langway circulated an attendance list, though, and CEU certificates are waiting for those who attended.
This is the report of our meeting on the evening of the evening of Tuesday, March 16, 2010. Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital Lighting and Supply, we met at their training facility in Upper Marlboro, MD. We had three inspector members, five associate members, an instructor nonmember and at least four student nonmembers.
Nik Dubish of Kelly Generator & Equipment, Inc., presented an interactive program of 1 ½ hours, talking about some of the issues that arise in specifying, installing, consulting on, and inspecting Generators. Nik used to work for Generac, and provides training as a regular part of his job. This program was approved by IAEI’s International Office for .2 CEUs (credited for 2 CE hours). Nik is certified as an Electrical Generator Systems Technician by the Electrical Generator Systems Association.
Nik, supported by Scott Norfolk in sales and Gary Fink, Kelly’s master electrician and NEC go-to man, discussed an entertaining series of slides taken in the field. Some showed well-done installations, others violations or simply bad ideas.
Before the training proper began, Scott led in with an overview of what their company offers. Yawn, right? Except that we did learn a couple of useful nuggets, useful for the contractors among us, and useful for the inspectors whom contractors sometimes turn to for suggestions. One is that they provide a fair variety of rental units, although not the very smallest. The other is their generator parts inventory; it is wide enough that they often can dig up obscure or obsolete parts. Scott talked very briefly–really--and then Nik took over.
These are some of the points that came up. They seem worth setting out separately in order to emphasize them individually.
· The rules for minimum clearances from outdoor generators to buildings vary. A common one is 5'. How to measure this is a matter in which inspectors differ: Gary is conservative, and insists of 5' from any point on the generator to any point on the building.
· There are cases, though . . . In one instance, in a historic district of DC, there was a Code requirement to install backup power. However, the property could not be modified because of preservation requirements. Therefore, the AHJ signed off on a generator being shoehorned in with nearly no clearance. · Some customers prefer visibility, others low visibility; some quiet operation, some the ability to confirm by sound that the units are operating. All these requirements can be accommodated reasonably well, but some don’t know enough to do it legally.
· Many generators are not designed to have their exhaust piped away. Modifying this, like modifying any aspect of the design, eliminates Listing protection and warranties. Nik showed us several examples of Generac units that were installed so that the exhaust entered HVAC intake vents. There were even more slides in which clearances were not established or maintained for adequate access to controls and battery compartments. Then there were some where combustibles came in contact with the exhaust. One allowed paper trash to fall in the vicinity of the generator, so it could be sucked up against the intake grill, or slide underneath the enclosure so that it could sit against the unit itself.
· Jim Wooten mentioned an inspection he performed in Annapolis in which he found the generator under a deck with the exhaust 9" from vinyl siding. Nik noted that their exhaust gases exceed 800 degrees.
· The nameplate of a generator lists the letter class of items such as the rotor. This indicates how hot the wiring can get before its insulation may fail. (The further along in the alphabet, the more robust.)
· In a shore area, Harry reported, authorities now require that generators be located 2' above mean high tide.
· Small creatures such as snakes like to crawl in under generators where it’s warm. Rodents like to chew on wires, at least those with pre-THHW/XHHW insulation. He has heard that this is because older thermoplastic insulations contain fish oil. John Marcio of the National Association of Electrical and Medical Imaging Manufacturers (NEMA) said [awaiting response]
· Within the generator enclosure, from the stub-up on, the wiring does not need to be enclosed within a raceway. Bushing to protect it are sufficient.
· When the power and control wires all have insulation rated for the power voltage, there still is a significant advantage to running them in separate raceways. If control wiring is run right against it in a single raceway and, in the course of the pull, a power conductor gets a kink, power going through the kink could induce a spurious signal.
· Smaller units use four control wires to start them, carrying binary signals. Larger units use two wires, and if the positive one inadvertently grounds, this can start the generator–or try to. If the motor is already running at a good clip, and the starter tries to engage without meshing, damage could result.
· Listing information always is located with the nameplate, by the disconnect, either inside or outside the enclosure. Jim piped up to mention that Annapolis requires that this information always be available on the outside.
· Diesel units have their own problems.
· Modern, low-sulfur diesel fuel breeds vermin in the water that’s part of the fuel. This gives it a shelf life of 6-12 months. If left untouched, it loses its bright clear red color and becomes useless.
· In addition to causing white smoke and clogging filters, they put out acidic waste products, which damage the engines.
· The fuel can be filtered and treated on site. The company has equipment to perform this operation, and can arrange with specialists to do the job when particularly large tanks need to be treated.
· Diesel is not light. Sometimes there is no place for the unit but on a rooftop, because of noise, exhaust, or just footprint. In such a case, the size of the tank that can be accommodated may be limited both by weight and by fire regulations. These can require pans to capture lost diesel safely in the event of tank rupture. A day tank on the roof with the main tank below pumping up to it is an option in some cases. Nik mentioned one job where pumping dfiesel up wasn’t acceptable, so they continued relying on a bizarre alternative. (If you’re curious about the details, give him a call.)
· There are legitimate, Listed dual diesel-gas units. However, there also are diesel units that have been improperly converted to gas operation. If it looks like a diesel unit and has a power pack on the side, it’s probably one of these, we were told. Enough on diesel.
· Scott confided that the units some manufacturers sell that are rated over than 100 kW do not have EPA certification.
· Gary mentioned that before selecting transfer equipment, he always requests a letter from the serving utility supplying the available fault current.
Ed Bihlear noted afterward that an arc fault article by a Bussman rep said that 65 kA commercial distribution may be safer to deal with than residential, which can run as high at 83 kA due to the serving utility’s transformers. (David attempted to follow this up with PEPCO’s media office, but received no response.)
Servicing backup power for a cellular phone tower is particularly nerve-wracking. Ice can build up on the dish even when there’s no ice below. A bit of a thaw can cause it to start breaking up. Especially at night, the first inkling you may have that it is falling is when you start being bombarded.
Jim reported that the BG&E utility no longer will service any equipment, gas or electric, that is located on a roof.
There was more than this, of course, but . . . you had to be there.
We decided at our Annual Meeting in January that we would be voting on changes to our chapter bylaws, changes that were proposed back in 2008. These were attached to March’s meeting notice. So members could be ready. Jim even prepared some questions to guide the discussion. However, the inspector who proposed that we schedule the vote did not attend, with the result that we were one short of a quorum under the present rules.
The meeting proper therefore broke up quite a bit earlier than usual, to be followed, as usual, by the social and educational after-meeting meeting.
Jim, Gary, and David all agreed that by signing a permit, a master electrician takes personal responsibility for the work performed on a job. If he doesn’t inspect it himself, he is laying himself open. Ed Bihlear mentioned that equipment is coming out from manufacturers with the new Arc Flash labels. The instructions set the approach distance is 41', so Ed simply insists that a draw-out circuit breaker be de-energized before he arrives. Because the arc flash boundary is 100', instead of inscribing a hazard category class, they write, “Seriously dangerous.”
http://www.energy.state.md.us/incentives/transportation/index.asp will link you to guidelines for two government incentive programs for those building Electric Vehicle-charging stations.
This is the report of our meeting on the evening of the evening of Tuesday, January 19, 2010, at Capital Lighting and Supply's training facility in Upper Marlboro, MD. We had five inspector members, five associate members, and four student nonmembers.
Because the changes discussed were based on the ROP, their content is subject to further modification in the ROC and then yet again at the Annual Meeting. Therefore, this report will focus more on the sweet nuggets contained in presenter Wayne Robinson’s–and the audience’s--asides. These were based on field experience and on proposed changes’ substantiations as reported in the ROP. This element is part of what leads these discussions to offer more of interest, in their way, than very straightforward seminars that closely follow, for example, the IAEI Powerpoint slides.
Here are some highlights:
Annexes are not part of the mandatory portion of the NEC; however, when referenced directly by a chapter, they can be. This may be underscored in the 2011 Code, but is true already.
“Power Panelboards” originally were panelboards that lacked a neutral, before the 10%-of-circuits rule was passed. The idea of pulling a neutral to every panelboard was applauded by several members. . They reported that they have seen neutral-less panels treated as though they did have neutrals all too often–with their grounds substituted.
Pete Bowers chimed in that a great many builders and homeowners buy jacuzzis without making sure the items they purchase fit into the intended locations in a way that leaves their motors and GFCIs/local disconnects accessible.
The original GFCI requirement in 1987 required this protection within 6' of each sink, regardless of type; it looks as though we will be returning to that concept.
It will be a wrench for some building owners if the panels serving their or their supers’ units no longer will be permitted to also serve as the house panels.
It appears that countertop receptacles will be forbidden to count toward the receptacles required for wall spaces, but wall receptacles will be permitted to count as the receptacles serving contiguous peninsula counters.
Floor boxes came up in the context of the proposed requirement that meeting spaces with movable partitions be served so that a partition would not cut users off from ready access to receptacles. David Shapiro polled those present regarding the fate of floor receptacle closers. Harry Langway sees them remaining intact, because the receptacles are never used. Pete sees the style using flip-open lids generally having them broken off within three months, and left off missing.
Wayne told a story about a call from a lawyer, who apparently was seeking support for his client’s contention that a fire had resulted from a certain type of negligence. Wayne eventually cut off his interest by presenting his off-the-cuff opinion that the fire was very likely to have been caused by three-prong receptacles having been installed in outlets lacking any grounding conductors (or, presumably, GFCI protection). He asserted that when there’s a ground fault in such a case, the yoke gets so hot carrying fault current over time that it gets the box to the point where the receptacle yoke breaks in half.
That is about as far as the NEC education went. We received sad news about a relatively new–but valued-- chapter member who will no longer be with us.
We slid smoothly into our business meeting. Pete asked about a vote on some bylaws changes that David had proposed many months ago. We agreed that they would be addressed in our March meeting.
Next, Pete mentioned a problem with inspection of fire alarm systems. In less than 40 hours–whoops–the state fire marshal would be meeting with those who probably should be inspecting their wiring.
Pete explained his concern further after the meeting, as being about: “. . . a new code section under 22-13, for fire safety - building code: MCER 5-06AM, adopted November 28, 2006. It establishes a requirement for issuance of a Fire Protection Systems License. That license is required to install, repair, test, modify or service any alarm system and/or equipment.
“The license is issued by the Fire Marshal's Office, with specific Nicet (National Institute for Certification in Engineering Technologies) documentation required as a precondition to qualify. Permits for the work activity are then issued by that department and inspection of the completed work is conducted by the Fire Marshal's Office. At present, the electrical inspection branch is not involved, leading to other problems of compliance in law.
“The reason for the new level of government oversight and control was that life safety systems have been installed and modified, their maintenance ignored or allowed to fall into inoperable condition--and the fire department had no control over malfunctioning systems in the public domain. This was an attempt to bring oversight into play at the major levels of system operability.
“The downside is that the process put the holders of Nicet documentation as the dominant player (which translates to the manufacturers or their local service organizations) to the exclusion of licensed electrical contractors. No requirement was stated that a journeyman or master electrician license was necessary for this work, in order to comply with other county law. Electrical contractors have been responsible for installation of system components forever, with final testing and checkout usually the domain of the manufacturer's representative. All that changed with this new regulation.”
No one spoke up to say they would be available on such short notice to attend the meeting.
Some days later, Pete reported that the fire marshal told that meeting's audience that he had had no one to help him prepare the regulation so as to coordinate smoothly with other departments or regulations.
Next, Wayne mentioned an upcoming meeting of the state committee regarding third-party inspector licensing and retesting.
Jim Wooten, President. Jim noted that he is thinking about
relocating close to the Pennsylvania border, at which time a
replacement would be needed.
Wayne Robinson, Vice President.
David Shapiro, Secretary-treasurer.
Robert Welborne, Membership.
Harry Langway, Programs, at least for a while.
There were no other volunteers for Executive Board positions, nor any to serve on a budget committee.
David reported that we are still pretty much busted.
Follow-up: We have been enjoying the hospitality of Capitol Lighting and Supply for some time. Steve Collins’s excellent suggestion at the last meeting, which was supported by a consensus, was that our leftover books pruchased for 2005-related seminars the be offered for Capitol’s use. This offer was carried out before the evening’s meeting convened.
Robert reported that he has changed over his membership category to Inspector. In addition to continuing to function as a contractor, and serving on Prince Georges Community College’s faculty, he has taken on their job of Electrical Supervisor and Plan Reviewer.
About 8:45, we adjourned.
After the meeting, of course, there continued to be some informal discussion.
This is the report of our meeting on the evening of the evening of Tuesday, November 17, 2009. Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital Lighting and Supply, we met at their training facility in Upper Marlboro, MD.
Wayne, our Vice President and also our evening's presenter, made a very prompt start to the meeting, jumping right in to a good hour and a half of solid Code instruction--and dialogue. His talk was thoroughly illustrated with slides he had prepared with PowerPoint for one of the handbooks he prepared and uses (and sells) in his presentations on the subjects. The give and take with the audience led the evening’s education/entertainment to be more freewheeling than a straight slide-driven presentation. Here are some highlights:
Wayne started out with Auxiliary Gutters, with side excursions to address rooftop installations, as well as other installations that call for temperature-related derating.
Much of the wiring run across roofs, he noted, just sits on pressure-treated wood rather than being secured to structural members. One of these days, he commented, all of these sleepers are going to blow off, with the right wind. Everything will land in the street. Inspection? In Baltimore County, he understood, inspectors no longer are permitted to go up on rooftops. The electrician signs a form saying the wiring up there was done to Code. CE-style self-inspection.
Moving back to ambient temperature derating, he brought up a slide presenting an extreme example. Suppose wiring–however long the run--normally would need to be 3 AWG, but the run ends with at least 10 feet in a boiler room with an ambient of 140 degrees. In accordance with 310.15(A)(2), the Exception not applying, the entire run might need to be upsized to 3/0. How, at least one member asked, is he to legally attach a 3/0 conductor to a 100 A circuit breaker designed for 3 AWG and 1 AWG for aluminum?
This stimulated a healthy discussion, resulting in a vote to seek an informal interpretation from NFPA, as a chapter. (The letter has been sent.) Ironically, Pete Bowers, a chapter member, has been the IEC’s alternate on CMP 6 for the last couple of Code cycles. It is conceivable that, had he been at the meeting, he might have been able to illuminate the discussion.
These were our questions:
· What does it take to break the requirement? Suppose
there’s a panel outside the boiler room, with one
overcurrent device. Could the wiring from there to the load be
3/0, and upstream 3AWG?
· If this would be inadequate, the panel being considered to contain a mere supplementary overcurrent device, how about upsizing both the upstream conductor and the device ahead of it by one size: could the rest of the run now be considered a feeder?
· Going in the other direction, if this sort of sleight of hand is acceptable to release the installer from having to comply with the requirement, why wouldn’t a simple junction box be acceptable to break the run?
Our question was not what an AHJ may decide based on the printed wording, but rather the intent of the Code section.
From there, we went to motor conductor calculations. Wayne mentioned duty rating as an example where the Code has found good reason to give designers a break on conductor sizing. Ed Holt, a former member and a welcome, frequent visitor, noted that the motor controller must have physical limits that restrict possible use of the motor, not merely settings. Furthermore, something as simple as a time clock is insufficient–it could be reset, or removed, or replaced.
Wayne brought our attention to overload requirements that are new in the 2008 Code. It’s not a big deal to figure out what’s permitted: The nameplate gives the class of motor, and then Table 430.32(C) identifies the maximum overload device.
Here’s a matter of interpretation: Wayne said that based on his reading of Stallcup, you can’t exceed the size identified from the table, even if your calculations might suggest otherwise.
We quickly moved on to transformer calculations. Here are some points he made.
If more than one overcurrent/disconnect is used for protection, the sum of their actual ratings can’t exceed what the maximum rating would have been had there been only one disconnect.
This next one raised some objection–from two knowledgeable men. One was Ed Holt, who carries serious inspection responsibilities indeed. Wayne commented that there are “five million” transformers out there with 400 amp mains but 500 Kcmil mains. He noted that technically, the wire isn’t protected by the overcurrent device, and therefore the design is illegal.
Both Ed Holt and Rich Panizari piped up, saying that sizing the conductors to the loads makes the practice legal. This brought Wayne to taps. He reminded us that restricting the primary length to 10' and the secondary to 15' keeps a tap no longer than 25' and permits us size it to the load. His next comment elicited some differing opinions from the audience. He noted that it’s awfully easy to go overlength. One reason is that runs never perfectly cross the space from where they enter to where they are connected, but follow structure. An even more easy-to-overlook one is that the tails inside the transformer and inside the overcurrent device cabinet tend to be overlooked in the count.
He added a final comment on allowances. He has never seen a fuse oversized to 250%, as technically permitted when necessary. However, he pointed out, it is necessary to keep the permission in mind when facing test questions.
Another snare he warned us of (as did Chuck Mello in the December issue of IAEI News) is that whatever the permitted sizes for separately derived systems’ individual grounding electrodes, once they are connected to a common grounding electrode it must be sized a minimum of 250 aluminum or 3/0 copper.
He focusing on feeder taps for his final segment. Wayne commented that when the conductors are sized at the full calculated rating on both sides of a splice, there’s no tap. Once even a single undersized conductor leaves a splice, it becomes a tap, and its length is limited accordingly.
Rich, Ed Holt, and Wayne engaged in some fun discussion about field options to allow the use of the 1/3 rating. Wayne pointed out that if we downsize the primary-side overcurrent device, it may trip. Ed suggested that this would tend to be due to inrush current, so you could adjust the trip setting. Wayne argued that this would require engineering calculations, for coordination.
After a bit over an hour and a half, we took a break, returning for the business/executive meeting.
The first order of business was for Charles Johnson, our new Programs Officer, to seek input as to how to solicit presenters for future meetings.
He did get a lot of the input he asked for.
· At the end of Wayne's talk, he mentioned that he has
a 2011 Code Change book or books in the works, and would be
willing to spend an evening in January—that's the meeting
on January 19—giving us another good hour-and-a-half.
· Steve Collins mentioned that his father was a fire commissioner for ten years. He and others speculated that the state fire marshal's office is concerned about electrical safety across the state. They might have comments for us on the current situation in Prince George's County. He will ask his father to contact the office for us, to find out whether we can get a program consisting of one of their representatives addressing us on the interface between the fire marshal and localities. Steve also came up with several ideas regarding a publicity campaign.
· However, Nigel Nisbeth, a brand-new member, had even more ideas, including a program where we invite members of the press to attend a discussion of how the current reduction in professional oversight of electrical inspections might be seen as affecting safety. At David's suggestion, Nigel agreed to try out the job of Publicity and Public Affairs chair, seeing to not only these contacts but also publicity for future events such as seminars. He will be coordinating with IAEI's International Office, to make sure that what we do is in keeping with their policies.
David reported that we are somewhat in the hole at the moment, the result of expenses incurred sending representation to the Section meeting. This will diminish with the annual Winter IO disbursement, though David will front the money to pay for our audit in January. Fortunately, most of our members receive our mailings via email, and we have enough postage to handle the remainder for some time.
Our 2010 fundraising will have to do a little better. Otherwise, we may have to rethink our representation on the Section Executive Committee, and with it the annual Secretaries,' Treasurers,' and Membership meetings.
We do have one small asset that has been sitting unused: a set of 2005 NECs, plus one 2005 NEC Changes book. While the list values total $400 or so, we are highly unlikely to use them in actually teaching a 2005 NEC seminar at this point. There were proposals to dispense of them by offering them online, and we were about to vote on this when Steve Collins came up with something better.
We have been enjoying the hospitality of Capitol Lighting and Supply for some time. Steve Collins’s excellent suggestion, which was supported by a consensus, was that the books be offered for Capitol’s use. This offer was conveyed when the meeting ended; Ken Cain graciously accepted.
Robert reported that he has continued to invite people to try us out, and some ask him for membership applications. Four current students accepted his invitation to attend the evening's program, and one, Justin Bagley, who just converted his Limited Master to a Full Master license after having taken Robert's refresher course.
About 9:30 we broke up and formally adjourned, not necessarily precisely in that order. At least two attendees, Ed Holt and Ed Bihlear, had to get up at 4 AM to handle their considerable responsibilities.
After the meeting, of course, there continued to be some informal discussion, including some war stories, so to speak, in the parking lot. Fascinating stuff.
This is the report of our meeting on the evening of Tuesday, September 15, 2009. Attending: three Inspector members, four Associate members, and one prospective member. Once again, thanks to the generosity of Ken Cain, VP Marketing for Capital Lighting and Supply, the meeting took take place around 6:30 p.m., at their training facility in Upper Marlboro, MD.
Not dark; not in fact night; but it certainly was stormy, and a challenging drive for some attendees. Furthermore, Jim, our President, had been called out of town; Charles, our At Large board member, was home recuperating from hip surgery; and even David, our Secretary-treasurer, was a few minutes late. Happily, those who did make it spent our time schmoozing comfortably. Once David arrived, Wayne, our Vice President, called the meeting to order officially.
Our meeting's speaker and topic were not been nailed down beforehand, for whatever reason; subsequently our new Education Coordinator, Pete, decided it would be best to give up the job and focus on his other commitments. As both David, our chapter secretary, and Harry, our former Education Coordinator, had understood that speakers had been scheduled, we waited patiently for them, as afternoon slid into night (and the storm temporarily abated).
Wayne mentioned that he always has PowerPoint presentations on Code topics available. Teaching with them may not be his bread and butter, but it certainly is a significant sideline.
He talked at some length about the hoops he has jumped through successfully in order to have his seminars accredited for CEUs in all sorts of jurisdictions. (He also talked about the woeful situation of inspection in parts of our area.) David mentioned an opportunity resulting from his having completed the editing of W. Creighton Schwan's final book, Behind the Code, except for some fiddly details. One of those details is that he recently received permission from NFPA to reproduce copies of the fronts of any NECs as illustrations. He will be inserting a great many of them, going back to at least the 1911 edition. Just as Oran P. Post entertains the Ohio Chapter with an assortment of old NECs, David could have brought in the images he has available.
We did make a firm determination that the next meeting will have a program, whoever needs to handle the duty.
Robert, our Membership Coordinator, brought up an enforcement question and got his answers. Nathan, an engineer now with a consulting firm but formerly an Orange County, CA IAEI member and a NRTL employee, introduced himself. David and several others complained about the lack of enforcement, which encourages illegal work.
Eventually Robert interrupted some grousing and discussion about low participation, about cumbersome new processes resulting in the need for non-employee "permit runners," and about new licensing requirements to give his report. Robert has gotten the impression that a fair number of people he talked to were interested in IAEI. Thirty showed enough interest to ask for membership applications. But nothing came out of his efforts, to our knowledge, except for member Steve Collins showing up. Robert has not let this stop him.
Steve spoke at length about his work; he has quite a special specialty. For decades he has worked on data centers. When their equipment is put together, it must be well over 99.% reliable: at least six nines. This is a challenge for the product manufacturers who want to remain competitive.
He talked about the early days of 400 Hz work. They knew nothing about harmonics or skin effect initially. He'd be called in the middle of the night to reset a breaker that had tripped despite being loaded well within its capacity. The next day he'd strip it out and find . . . nothing.
They learned that excess heat was the culprit, although they didn't know why it should be present. They responded empirically, with fans and eventually with different setups entirely, ones that allowed far better heat dissipation from a breaker.
Steve spoke a bit about the progression of data center cooling designs--air-cooled to water to air again; fans to tents to their more-efficient successors. Still, an important part of the remedy was modified electrical designs. Paralleled conductors? What's he or she saying? (I guess back then it was pretty certainly "he.")
The NEC offered little guidance. Steve and his colleagues found that part of what was needed, in fact, violated NEC rules. Always, though, they kept safety in mind, and eventually the practices that they had found necessary to follow became incorporated the NEC. Inspection of these data centers was no simple thing, anyway. He'd get a call from the jurisdictional inspector telling him to meet the guy downstairs at such and such a time, though, and shepherd him through the security gauntlet.
Steve was a fun "presenter." Eventually, the meeting broke up at about 8. We'd been going for something over an hour and a half, and generally having a pretty good--and useful--time.
Our meeting took place on the evening of Tuesday, May 19, 2009. Once again, it was hosted by Capital Lighting and Supply, thanks to the generosity of Ken Cain, their Vice President for Marketing. Attending were 4 inspector members, 6 associate members, and 6 nonmembers, plus our two speakers.
Having a quorum, we held our annual election. The same officers were re-elected, with one exception. We have a new Education Coordinator. After working well and hard to serve the chapter, Harry Langway–a member of the Chesapeake Chapter who lives on Maryland’s Eastern Shore–found a volunteer, Pete Bowers, to take over finding meeting speakers. Harry provided, and will continue to provide, guidance to help Pete get started with candidates for our Fall programs. Besides some familiar, and very good, speakers, we may have enjoyable teasers, such as a brief introduction to ANCE, a testing laboratory that is in the process of obtaining NRTL certification.
Secretary-Treasurer David Shapiro circulated a CPSC notice concerning a recall of some Fluke clamp-on meters. Download site: http://www.cpsc.gov/cpscpub/prerel/prhtml09/09222.html. Before the evening was out, members picked up previously undistributed CEU certificates acknowledging their attendance at the educational talks enriching meetings before March’s. We hope to get dual-signatory March CEU certificates to September’s meeting, along with those for attendance at the educational portion of May’s meeting.
Finally, Pete brought up some news about Eaton/Cutler-Hammer. First, Tony Crimi, their representative who used to attend our chapter meetings, has retired, and it was not clear who is replacing him. Second, they have developed extranet programs to enable both distributors and contractors to obtain price and availability information about their products. Pete noted that this could be especially handy for contractors who try pricing jobs evenings and weekends. One glitch is that even their distributors seem unaware of the program. Another is that to be able to participate in the program, you need to fill out an application that includes the name of your local rep–that’s the person through whom they supply you with your access ID. Pete had not yet been successful in getting answers. David contacted them in the name of the chapter. Apparently no one is going to be quite a local as Tony for now. They told us that the contact person, both for their extranet and for any chapter support from Eaton, now is Alesia Davis, in the Baltimore area. For information about the contractors’ extranet program, you can go to http://www.eaton.com/EatonCom/Markets/Electrical/BusinessPartners/Contractors/98067397
A number of members, and non-members, showed up early for some additional free training, courtesy of Southwire. Southwire’s representatives may be back–perhaps next year–to address one of our meetings; this is up to our new Education Coordinator. However, this report is not about the pre-program but about what took place at our meeting on May 19.
Harry Langway had lined up another fine presentation:
Meters and Electrical Measurements.
Besides giving us a hell of a show, and providing solid information, attending this yielded paid-up IAEI members another full two hours of CEUs, as authorized by the IO.
Question: When we need to rely on meters to keep ourselves safe and make sure that installations are functioning properly, who do we want go to to get the lowdown about meters--someone who's had a course or two, and otherwise figured things out by the seat of his pants, or someone who knows meters inside out?
Brian Blanchette is not only a technically astute head who thinks things through, does his own research, and is not overly shy about sharing the results. He also is accessible and personable, and a more-than-competent writer and teacher. Ideal’s Tests and Measurements Manager, the man designed some of the meters on the market today. It is very hard to find somebody with his experience.
Brian discussed the correct way to use various digital meters,
but started his talk in such a way as to accommodate even
walk-ins who might not have the background of people who’ve
studied, been in the trade. He began with basic electrical
theory, and quickly went on to the implications of voltage drop.
He thinks of impedance more in terms of available fault current
than of VD, because that is key to protective equipment being
enabled to function. He moved on to line-to-neutral voltages, and
a damned sight more–including some big surprises, pearls
dropped along the way. Even members of the audience who might
have felt lukewarm toward hearing a spiel focusing around one
particular manufacturer’s line of meters had plenty to
Ron Greenfield from O.T. Hall accompanied Brian. In addition to his day job as a sales representative, he is an instructor with the I.E.C. We heard an amusing dialogue between him and Pete, who has bought several meters from him. Brian, Pete, and of course Ron spoke with one voice on the need for inspectors and contractors to buy the various meters, and adequately sophisticated versions of them, to be able to scope out their jobs adequately.
Time to provide some details. Brian mentioned combination-type AFCIs early on, talking about how the first two brands available–Cutler-Hammer and Square D had very different designs from the later introductions, manufactured by Siemens. The latter also include those they manufactured but branded as G.E. and Murray.
Whatever their design, AFCIs, like any other protective devices, require enough current to flow to cause them to operate within the critical time frame, however the latter is specified. This is where the critical nature of available short-circuit current comes in. This factor brings us to the main approaches to minimizing impedance: reducing the number of series connections, each of which is going to be characterized by a certain amount of impedance; and sizing conductors appropriately for length of run. Furthermore, in performing distance calculations, he reminded us of the need to consider the full round-trip length of a each circuit, not just the one-way distance.
While the present generation of testers require the presence
of voltage to get an adequate picture of circuit condition, Brian
noted that the IEEE standard is phrased in different terms:
recommending that we keep the total impedance over the length of
any one conductor–that’s conductor, not round-trip
circuit–to a quarter of an ohm. Ron chimed in to point out
that some prefer to keep conductor impedance within a
more-generous limit: one ohm.
This does not need to be left so abstract. For one example, consideer this: 14 AWG copper runs 2-2 ½ ohms per 1000 feet.
Now consider an older or at least cheaper single-family residence. Suppose there is no central air conditioning. Suppose also that one 15 amp circuit wired in 14 AWG cable takes care of the receptacles daisy-chained all over the house. Unfortunately, this is not uncommon. If there’s no central air, it’s very likely that if there’s any money at all there’s a window air conditioner in a bedroom. Quite commonly, that bedroom will be located at or near the tail end of the circuit. Now we have a relatively high-impedance circuit with a compressor trying to draw up to six times its normal current each time it starts. What happens if we retrofit the house with AFCIs? They may be almost useless.
Brian also expressed dissatisfaction with the tests presently in ANSI/UL standard 1699. Rich Berman, P.E., our U.L. Regulatory Engineer, said this when he viewed the comment after the meeting:
“. . . it is correct that the proper way to test an AFCI device is to push the AFCI TEST button. AFCI indicators can be a convenient way to determine if an AFCI is on a circuit, but some AFCIs may not trip when subjected to the pulses from an AFCI indicator. [Ideal Industries’s tool for checking AFCIs technically is “an indicator,” not “a tester”; as Brian noted, the only official way to test an AFCI is to push its TEST button] If the AFCI stays energized when used with an AFCI indicator, it does not mean that the AFCI is bad and should be replaced. UL 1699 does not require the AFCI to trip when subjected to the pulses of an AFCI indicator.
An AFCI is not an overcurrent protective device [this is not to deny that an AFCI circuit breaker is an OC device], and is designed to recognized unwanted arcing faults. One of the tests includes a razor cut on an insulated conductor (called the point contact arc test; technically, the "razor" cut blade is specified in the standard as 0.05 in. (1.27 mm) thick which is not a razor. Sharpening to an razor edge is optional if agreeable to all concerned.), but there are several tests for operation inhibition and unwanted tripping, including inrush current, normal operation arcing, non-sinusoidal waveforms, multiple loads, lamp burnout, and immunity (EMC, RF, etc.).”
Let's get back to Brian's warning about the limited value of AFCI protection on a long multi-outlet branch circuit that ultimately feeds a window air conditioner. One of the assumptions intrinsic in the design of all AFCIs, he warned us, is the availability of at least 300-400 amps of short-circuit current. Later in the evening, he commented that a decent residential short-circuit current availability figure is 300-600 amps. One You-tube.com site, he commented, used to show a homemade, 120 volt arc furnace fed by non-defective AFCIs that fails to show any inclination to trip. To forestall disbelief in the possibility of such a project, he commented that for jollies he himself created a arc furnace connected to a household circuit as a kid, using carbons from a D cell (shaped as needed) wrapped with copper wire, a dish of saline solution, and not a whole lot else.
Brian was not saying that AFCIs are useless, or a bad idea. He put it this way, after the meeting was over: “. . .it is very difficult to reliably filter out nuisance trips without filtering out real events. . . I am pretty sure the things can be effective. The commercialization of the product was not necessarily kind to the technology, but then, it rarely is. . . Nothing is perfect, and the Combination Arc Fault Circuit Interrupter breaker does detect arcs that other breakers cannot.”
The question of how you know whether an AFCI is defective he answered easily: push the TEST button. If it trips, it’s good. This is a much more reliable test of whether it is defunct than trying to trip it with an external arc, because of issues of circuit impedance. To the greater surprise of many in the audience, he noted later that he has found consistently that AFCIs are good for about 75 trips– the number must include those caused by pushing the TEST button. After this, they won’t trip when you push the TEST button, and are due for replacement. How effective they will be in responding to a particular arc fault is another matter, depending on design of AFCI and circuit.
Moving back to his main subject, he acknowledged the challenges in testing circuits fed by them. As he described the elements to branch-circuit testing, he–and Pete--discussed the use of testers to tease out various aspects of these questions. Brian mentioned, and showed bits of, a White Paper that he wrote, titled, “The Electrician’s Guide for Testing Branch Circuits with Combination AFCI Circuit Breakers." It contains a decision tree, focusing on the use of his company’s test instruments. It was a relief to read that when the AFCI trips only in response to simulated problems in the outlets closest to the panel (or only in some outlets generally, but not all), the problem is most likely caused by loose wires or connections–or by tests made at faulty (high-impedance) wiring devices. Another interesting comment, at least for people who have not discussed design with representatives of various manufacturers, was that he has found different AFCI circuit breakers respond differently at low current levels. One point he emphasized was his reason in naming it “The Electrician’s Guide. . . “ rather than the inspector’s: most testing has to fall on the installer, not the inspector. Pete had talked of coming in, red-tagging jobs for violations, and leaving, repeatedly, until contractors finally reached the point where they tested their own work adequately before calling for inspection.
On a more-general note, Brian commented that most of the testers we are likely to be carrying are rated as Category 3 or higher–and they need to be. This rating means that they have been certified as safe up to 600 volts, good for testing anything normally found indoors. Category 2, on the other hand, is suitable only for use at a branch circuit outlet itself, and not upstream.
He went over the elements in testing branch circuits in some
detail. To summarize, you review:
1) The physical structure of the circuit, which includes confirming correct polarity at outlets;
2) The quality of the voltage supplied;
3) Neutral-to-ground voltage, which varies depending on load and circuit impedance–the latter hinging in part on distance along the wiring from the common bounding jumper;
4) Voltage drop; and
5) Possibly actual impedance.
He also urged the use of thermal imagers to answer certain questions, noting that the price of at least some new units has plummeted. The discussion of thermal imaging–in some but not all cases related to the sorely-uneven balancing of loads, especially loads characterized by triplan harmonics, across phases--led to a comment about three-phase neutrals. He emphasized that these often are inappropriately downsized, even though doing so may follow the rules for derating that is permissible when they are not considered to be carrying significant current. In fact, though, they should be increased, to compensate for carrying sizable additive current from more than one phase.
The only standards addressing Total Harmonic Distortion set standards for maximum voltage, even though voltage distortion exists as a response to current distortion–to loads. In very large systems, up to 8% THD may be acceptable; almost everywhere else, 5%. In hospitals and airports, though, 3% is the maximum. The solution to these problems in three-phase systems is twofold: don’t put all of the distorting loads on one phase; and oversize the neutral.
The examples were quite entertaining. On one job Pete’s meter reported a false ground. Rather than check for bad connections at one place and another and another, searching slowly upstream, he was able to go to the panel, where the neutral conductor’s termination was loose. On another site that turned out to be suffering from just this problem, Brian used imaging to determine that it was what caused a panel overheat badly. With each turn to the inadequately secure screw–and it took several--the readings returned closer to normal. “Don’t retorque, because you’ll extrude the wire”? This case was an exception.
Switchgear normally is rated for installation in maximum 40 deg C ambient environments, and loads are permitted to add up to 30 deg C additional. When a conductor is glowing, what do you do? One bank’s system did just this, and if they had shut it down, the data in their computer system would have been lost. While they hastily downloaded it, the bank’s carbon dioxide fire extinguishers were paraded to the panel by a bucket brigade of employees, moderating the temperature just enough until they could close it down.
Backing off from the horrible examples, Brian talked in more general terms. Fortunately, he noted, most problems are the result of gross mistakes, such as neutral-ground bonds downstream of the Main Bonding Jumper. This is worse, he noted, when it occurs in single-phase wiring utilizing the neutral, because with three-phase at least there is the possibility of some return current flowing through the other phases. Perhaps another corollary of the concept that the causes of most problems are gross is that meters don’t have to slice the second too fine in their sampling. That yielded this aphorism: “No instantaneous readings carry quality information.”
In discussing what sort of readings can be useful, he touched on the difference between normal meters and those testers that can report peak current. This led him to an aside on the history of electricity generation and the dispute between Edison and Tesla, with Westinghouse as Tesla’s sponsor. Edison proved that AC could be dangerous, claiming that there was no measuring AC, and setting limits. An excellent showman, he demonstrated this not with a dog-and-pony show but with rather more of a circus. He electrocuted an elephant using AC, and later donating an AC electric chair to the State for executions.
Tesla responded by developing a system to measure AC. It couldn’t be simple averaging, because if you average a quantity that alternates evenly between the same level above and below zero, you get zero. Instead, he conceived of RMS (Root-Mean-Square) figures, and figured out how to measure them.
Oh, there was lots more, but . . . you had to be there. The meeting ran past 9 PM, though not quite as long as some. Our remaining meetings this year will take place on Tuesday, September 15 and Tuesday, November 17.
Attending: around 20 people, including at least 5 Inspector members, 5 Associate members, and 8 or 9 nonmembers, apprentices who showed up for part of the evening, at the urging of their instructor, Membership Chair Robert Welborne. Unfortunately, the roster disappeared in the course of fax transmission from Past President Wayne Robinson, who stood in for Secretary-treasurer David Shapiro, who was sidelined by vertigo due to an inner-ear malfunction. A number of long-time members who don’t often attend made it in, and several reported afterwards on how valuable they found the mini-seminar.
The group enjoyed a fine two-component presentation by Michael Johnston, former IAEI Director of Codes and Standards, who now holds a similar senior position with NECA. The first part reviewed grounding and bonding of separately derived systems. The second element looked ahead--extensively--at Proposals for Article 250 of the 2011 NEC that seem likely to be accepted.
Financials and Seminars
We are operating without an updated Board of Directors. In accordance with our bylaws, this means our present Board remains in place. While out books continue to pass the annual audits, we also do not yet have an approved budget overseen by a budget committee. The information submitted by David Shapiro previously in the draft budget remains relatively accurate at this point, although we are better off by what we netted from Wayne Robinson’s first Code Update seminar.
Unfortunately, the Grounding and Bonding Seminar he offered in April was not sufficiently subscribed, and had to be cancelled. Checks were returned, with thanks.
At present, we are searching for a new bank account, as our long-term account has instituted a maintenance fee that we could easily incur each month for falling below the minimum balance. While at first GMAC Bank seemed very promising, David, as chapter treasurer, has been forced to consider it the least safe bank he has ever dealt with, only in part because their representatives repeatedly failed to keep agreements. As of late April, David is still in the process of determining whether either of two other banks, with local branches, can serve our needs.
6 Associate members;
2 Inspector members;
Plus our presenters–3 visiting nonmembers
We got started around 6:30, after a pleasant half-hour or so of informal conversation–following on a very homey period, for a few early arrivals, of even more informal conversation in the lobby with Ken Cain, who has extensive experience in this industry. Ken, incidentally, had left a number of flyers in the meeting room, inviting us to join a free half-day product training session to take place at their facility.
Without any delay at all, Harry Langway, our Program chair, welcomed Mark Phipps of manufacturers’ representative Electrical Sales Associates, Inc., and his colleague Tom Kidwell introduced our speaker, Dave McBain of Littelfuse, who had flown in the day before to avoid the Inauguration traffic.
The first item we concentrated on was arc flash and arc blast–the big reasons to reduce available energy at points of access to an electrical system. Dave displayed one slide showing daunting numbers: good fuel for those of us who want to make a point to scoffers about the importance of doing things right.
More than 1000 annual deaths due to electrical accidents;
More than 2000 workers sent to burn centers each year with severe burns due to arc flash/blast;
Among qualified workers, 80% of injuries and fatalities due to arc flash/blast; and
Annual costs to employers and the nation.
We proceeded to learn all sorts of things about fuses, and overcurrent/life safety protection generally, including but certainly not limited to series-rated systems, and to current-limitation generally.
He started out with some very brief film clips showing arcs. One was a 30-second video caught on a meatpacking plant’s security camera over the weekend of 5-6-03. We saw three untrained, unprotected men--wearing nylon on their heads to keep stray hairs out of foodstuffs. It showed the flash, it showed the men staggering afterwards, confused, with the nylon melted to them. One didn’t even realize that his shirt was aflame.
Electrical workplace safety requirements associated with arc flash/blast come out of NEC 110.16, requiring labeling; the OSH Act, CFR 29 1910; and NFPA70E. 70E tells how to calculate arc flash.
IEEE 1584 is an optional guideline, an alternate means that can be used to calculate some arc flash calculations. Most programs of protection are offered at work sites, by employers. Dave mentioned that Proctor & Gamble has an internalized program re training for protection against arc flash/blast; makes it one of the better places to work.
Current-limiting means letting at most ½ of a cycle’s energy through before interruption is completed.
Non-current-limiting means letting at most 6 cycles through.
This is, of course, with AC loads. He went to the trouble for us afterwards to confirm that they are similarly, though not equally, effective with DC loads. In the words of Kenneth Cybart, Littelfuse’s Senior Technical Engineer, “DC circuits are harder to extinguish than AC circuits. How quickly a fuse reacts to DC short circuits or DC arc flashes depends on the X/R ratio of the DC circuit. We would have to test our fuses at different X/R ratios and DC voltages to see how quickly they can extinguish the current, and minimize the energy. But, in general, AC current limiting fuses react faster in DC circuits than non current-limiting fuses. The IEEE and NFPA are now working together to come up with mathematical formulas to determine how much incident energy a worker may be exposed to under DC conditions, but the results may not be known for a while.”
Ken also pointed out that generic arc flash warning labels, while still meeting the requirement in NEC 110.16, are inadequate for compliance with the 2009 edition of NFPA 70E. The latter calls for warning labels field marked with incident energy available or required level of PPE.
Even with AC, protective devices offer differing levels of current-limitation. Their RK1 fuse, for example, lets through less than their RK5 (though it fits the same fuseholder).
Most of today’s fuses are tested for up to 200kAIC. Some old ones are manufactured to a different standard: 5 or 10kAIC. Dave asserted that CBs let through more energy the bigger the fault, fuses less.
Utilities, of course, give you the starting point for any AIC calculations. Harry Langway noted that PEPCO will give you fault current, but he has not been successful at pulling similar information out of BG&E.
Dave mentioned two helps for people in the field. 1-800-tecfuse is Littelfuse’s technical help line, which ring you through directly to a person who will field your fuse-related question, whether you are dealing with their fuses or not.
He also mentioned a service his company offers, performing fault-current analyses at facilities.
He also distributed a few handouts, theoretically focused solely on fuses, but some in fact applicable more generally. For instance, the Littelfuse brochure (Form PF992) “Using Current-limiting fuses to increase short circuit current ratings of industrial control panels” has a great sketch on P. 4 (which we were shown as a slide) showing graphically how a current-limiting device reduces let-through energy.
He also plugged their elevator (shunt trip) panels, and their (Selective) “coordination panels,” which include breakers (yes, really!–single pole C-H Quiklags) containing integral series fuse protection, designed for use to help comply with requirements for certain Special Occupancies, Conditions, or Equipment. In the 2008 edition, these are: Healthcare Essential Electrical Systems (NEC 517.17(C)), Elevators (NEC 620.62), Emergency Systems (NEC 700.27), Legally Required Standby Systems (NEC 701.18) and Critical Operation Power Systems (NEC 708.54); also for use in orderly shutdown, as an option for Electrical System Coordination NEC (240.12(1).
There was a product selection guide . . . all the sorts of things that you would expect from a manufacturer given the opportunity to address an audience.
Finally, he handed out a few sets of “collector cards,” plastic-laminated forms, a little like unbound Codechek (TM)s. These of course are thoroughly oriented around Littelfuse products, where applicable, but the coverage extends beyond those, with a few pages, for example, devoted to PPI.
With so many absent due to the inauguration, we addressed no business–neither nominations and election, nor review of new and clarified requirements from the International Office, nor consequent selection of a budget committee, nor discussion of possible bylaws changes, nor publicity activities for the seminars that are planned. The required Treasurer’s Report was made available in writing, but only Jim looked it over. One member took home a scholarship application, promising to bring additional copies to our next meeting. Our March meeting, presumably, will serve as our Annual Meeting. If we lack a quorum probably it will make sense to handle the necessary votes by mail.
Here are the next couple of Code questions and answers, as promised.
1) Ampacity Exception A 200 amp MBR service panel serves a single-family dwelling. A generator also serves it, but not as a separately derived system. It’s only a 3-wire transfer switch; the neutral remains isolated from ground, as the cable used is 2 AWG aluminum SER. The switch feeds a 125 amp panel for which we need to select a main. The load fed via the transfer switch is 80 amps or less. Can we apply 310.15(B)(6) and use a 100 amp main?
No--this is not the entire load.
No: permitted, certainly, but not required. Isolated power systems’s specs are only explicitly discussed, in considerable detail, in one location.
In 2008 (overlapping with the end of 2007) we received $669 from the IO. (In 2007, overlapping etc., $734)
In 2008 we expended $90 for bookkeeping, thanks to the generosity of Pam Panizari. Ditto previous years.
In 2008 we expended ~$90 on copying and mailing. (2007, $266.)
In 2008, like 2007, we expended $17.45 to renew our domain registration and forwarding service. (I donated the actual hosting, with a page on my web site.)
In 2008 year we paid $89.46 toward a partial “I am Safety Smart” kit from the IO, with Peter Bowers and David Shapiro promising to cover the rest of its cost. (In 2007 we contributed $100 toward the Leukemia & Lymphoma Society as a memorial for Art Hesse.)
In 2008 we paid $1263 to send me (& wife) to the Eastern Section Annual Meeting, where I provided our representation on the Board of Directors. Lodging, including deposit: $9; registration, $300; one-way gas $27; One meal $28. In 2007 I ate the costs, because the chapter was rocky financially.
In 2007 we also paid $70 for groceries, for meeting refreshments. This experiment was not deemed worth repeating. In some previous years, Dick Bissell, who has since retired from the industry and dropped out from IAEI, periodically donated trays of meatballs.
Realistically, I don’t know what we might take in to balance the books.
Here’s what I can say, rather dourly, based on what I do know:
So: IO Disbursement, $700.
Pete Bowers offered to kick in a third of the cost of the “I am Safety Smart” kit, which amounts to . . . $89-odd.
Judiciously, $50 for copying and mailing, IFF we don’t
have to mail paper ballots to our inspector members to get a
critical vote, and don’t do a mass paper mailing of a
meeting flyer, but just send out paper meeting notices five times
a year to those few members who don’t use the web.
$18 again for domain registration.
$1500+? for representation at the Board meeting. Our rules say its normally the responsibility of our secretary to represent us there, and our tradition has been to cover the full cost of attendance for secretary and spouse. 2007's meeting was a lot closer to us geographically than 2009's will be, and I see the associated expenses other than travel rising, not staying level. I have asked the Green Mountain Chapter for any information they can provide, but have heard nothing so far. I know that I may not be comfortable personally covering the costs of representing us.
$100 Surprises. I suggest this as a minimum cushion to cover unanticipated miscellany.
Total Expenses anticipated ~$1700.
Income anticipated ~$ 790. at best plus future seminars' net.
Net: - ~$900 shortfall
The December 2008 IO distribution turned out to be $289.-
Petty cash ~$0
Checking ~ $1005.-
So we seem to have liquidity. Round it down to $900 to cover miscellany, including the annual auditing fee. However, this figure still is somewhat illusory. . .
We owe: $525- for prepaid seminar registrations by Charles Johnson, Pete Bowers, and Jim Yeoman. True, none of them is insisting on repayment, and at least some have generously invited us to treat the registration fees as contributions. Still, we do owe them, at the least, the ability to apply the money toward future seminars–figures to be subtracted from our anticipated gross income.
Preliminary Status Evaluation: Cash flow deficit anticipated: ~$0. minus any future seminars' net.
Theoretical cash flow deficit:$525. minus any future seminars' net.
We own a small box of 2005 Code books and one 2005 Code change book (changes from the 2002 NEC, of course). Value maybe $400.
Net status if we liquidate that resource at valuation as well: $500-$400= ~$100 deficit -February seminar net.
Potential Additional Sources of income:
Pete generously offered to teach a master exam prep class co-sponsored by the local IEC chapter and us; this could bring in money–easily enough to cover the potential deficit. This did not happen.
Wayne very generously offered to co-sponsor a number of seminars, publicized by notices to his many former students, and split the income with the chapter–potentially thousands. As a result of the one that took place, we are not facing a serious deficit. Still, as of early March, 2009, while many have expressed interest, this is not yet true of sign-ups.
Further successful seminars could put us handily ahead, back where we were some years ago.
Hence the budget I offer must consider a theoretical deficit on the order of $500, minus future seminars' net, if we don’t generate additional income as we have in the past.
There are two simple ways I see of resolving this and balancing the numbers, in the event that the theoretical should turn into the actual. One is to rely on the good grace of those who registered for seminars that had to be canceled–all loyal members--and just not concern ourselves about that $500. The other is to set Eastern Section participation on hold. If we indeed bring in more income, fine; proceed as planned, or even get behind more educational and charitable activities. If not, either I see whether I personally can eat the cost of going there, as I did last year; or a substantial part of it. Either would be harder this year. Another is that we find someone from this area who plans to go anyhow and then we figure out a way that will allow him or her take my place; or we simply don’t take our place at the meeting.
There might be ways I can shave the cost, too. This year, for example, some hotel slight-of-hand enabled me to save us over $100 in room costs. It was perfectly legal and ethical, and fortunately, minimally inconvenient. Conference hotel: $255/night; hotel next door, $143/night for the night before the conference, when I had to be in town in order to make the morning’s board meeting.
I not only represent our chapter but chair the section’s bylaws committee, and provide secretarial assistance to the American Council on Electrical Safety (ACES), which is IAEI's guest. However, the Bylaws committee has two other members, and even with respect to the committee, my participation is not essential. (After all, if we should request a change in our chapter’s bylaws, we have to be recused from participation in that particular decision by the committee.) As for my support of ACES, it is not a chapter matter, and is provided only as available.
If we subtract what was paid toward canceled seminars, we come very close to even, assuming that IO disbursements don’t drop.
If we subtract the entire figure budgeted for Section participation, we do come out ahead for the year.
I do believe this covers us against reasonable contingencies.
Submitted February 2009.
Leave the Capitol Beltway at Exit 11A onto Route 4,
Pennsylvania Avenue South/East.
Now go about a tenth of a mile and then turn Left at the first light, Westphalia Road.
Next, take an almost immediate Right (just before the Citgo gas station) onto Pennsylvania Avenue’s Service Road.
Just as a location pointer, Sunbelt Rentals is located at 8400 Pennsylvania Ave.
Drive directly by Sunbelt Rentals and take the next Left, onto Pepco Place.
Travel to the end of Pepco Place - Past the Mid-Atlantic Regional Council of Carpenters, about 1/10th of a mile, and drive into our host’s parking lot. Parking is immediately in front of their building, on either side.
Washington Chapter meeting November 18 at our new location, 8511
Pepco Place, Capital Lighting and Supply’s warehouse and
training center, courtesy of Capital’s Jordan Laycook.
6 Associate members;
3 Inspector members;
Plus our presenters--2 visiting Inspector members
We got started around 6:30, with a brief facility tour. After this, Chapter President Jim Wooten prayed, and then decided to put off the scheduled business meeting in order to proceed with the evening’s featured speakers.
Code Making Panel (CMP) 7 Member John Cangemi, from UL, and CMP 1 Chairman Gil Moniz, from the National Electrical Manufacturers’ Association (NEMA), kept us glued to our seats. They talked with us for the better part of three hours about not only the 2008 NEC but the evolution of the rules, going back multiple Code cycles; and also about product standards, listing, CE marks, and products that need to be installed and inspected despite the lack of explicit Code coverage or Listing.
Some rules, they noted, have requirements that flipped back and forth form one Code edition to the next. Swimming pool power is one example, with GFCI protection required or not depending on the use of hard-wiring versus twist-lock receptacles in progression from 1999 through 2008.
Gil’s first challenge of the evening came when he casually mentioned that New York State enforces different electrical codes depending on whether a job is residential or commercial. David Shapiro asked how this contrasts with the situation in Ohio, which received rather bad press in IAEI News. Gil explained that historically in Ohio, a review committee had examined and then recommended acceptance of each NEC revision, as representing the best doctrine available. This time, however, politics had intervened after the fact, causing them to backpedal. In New York State, on the other hand, the legislature has accepted the International Code Council’s documents, the International Construction Code (ICC) and International Residential Code (IRC). The IRC defers to the 2002 NEC where issues are not addressed in the IRC, while the ICC has been updated explicitly to reference the 2005 NEC.
Jim commented that this would be a horror for an inspector; Gil agreed. Furthermore, he added, all license tests are based on the 2008 NEC, which isn’t applied at all to inspections. Gil followed this with an example where complying with the NEC will leave a job in violation of the Code in force. The ICC’s Existing Building Code relaxes the electrical requirement for locating receptacles. On the other hand, to address service it defers to the IRC proper. Here comes the problem. Consider a building with a stone foundation, and a service at the bottom level. The NEC relaxes the requirement for headroom at 200 amp or smaller services in existing buildings. However, if you are replacing service equipment under the IRC, there’s no such exception.
Another example he pointed out where some irregularity is found is Philadelphia. Pennsylvania adopted the ICC for electrical work, but Philadelphia enforces the NEC. One little step they happened to omit is to apply to the Department of Labor and Industry for an exception to the statewide rule.
In Maryland, Gil noted, electrical inspection is generally in good shape in terms of its basic reference document: at least the NEC is the accepted standard. This is thanks to the office of the State Fire Marshal. Wayne Robinson noted that there is a lot of pressure on the Fire Marshal to budge, though.
Here is where Gil and others started to discuss the politics of safety. One meeting in Rochester, he noted, was packed with firefighters in uniform seeking to have a sprinkler requirement added to the IRC. Even the building officials who might have supported the requirement voted against it because they felt uncomfortable with the pressure from this group. The next time, in Minneapolis, even more firefighters attended the meeting, but not a uniform was to be seen. This time the sprinkler proposal passed, and so the 2009 IRC finally incorporates this requirement.
Pete Bowers noted how politics screws up safety efforts in DC similarly. For 15 years advisory committees have looked at ways to improve the situation, and he’s sat on most of them. He’s seen how those with power resist giving up authority, even when they don’t have the expertise to make the best decisions.
Now Gil moved on to an issue that has come up as the result of utility policies around the country. Increasingly, utilities shift substations from their own ownership and responsibility to that of their larger customers. In consequence, jurisdictional inspectors become responsible for passing on these installations. Formerly, the work was guided by the National Electrical Safety Code, the NESC. Most jurisdictions, though, do not specifically adopt the NESC into law. While Section 90.2 used to have a fine print note suggesting that we look to the NESC for guidance, even this is gone. What’s an inspector to do?
One answer we were offered is to ask the owner what ANSI standard the equipment was built under. Ultimately, where the NEC is mum, we need to evaluate whether its installation complies with that standard. If the manufacturer is known and reputable, a call to them will supply lots of handy information. The manufacturer will be able to identify the project name, and locate the drawings and the engineer responsible for them.
John pointed out that going to the AHJ for initial concept review helps a lot. None of the inspectors present, though, offered that service. Wayne noted that regardless of which side of the service point high-voltage equipment is located on, he lays responsibility for such equipment installed in Prince George’s County on the serving utility. Tony Crimi said this is what Eaton generally sees.
Continuing to look at Article 90, Gil talked about the changes from the 1993 NEC forward in the description of what installations are not covered. Is there a laundry list plus an fpn, no fpn, does it add locations covered by whatever agreements putting them under utility control, or, in accordance with a proposal by Wayne accepted in the 2008 code, remove the term “or other agreements” so that any lighting installation that a utility wants exempted from NEC coverage and AHJ inspection at least has to be covered by an easement registered with the County. Gil noted that there are quite a few proposals to change it again.
Wayne expressed concern over agreements regulated solely by a Public Utility Commission (PUC), because PUC appointments are political, members being selected by the governor.
Gil moved forward now to Article 100. “Clothes Closet” now is defined, under the 2008 NEC. However, to Gil it is clear that this definition can be applied to inform the judgment of inspectors working under earlier versions of the NEC, because it is a definition, not a new rule.
David broke in here, asking where else this approach makes sense: is it limited to Article 100 definitions? We agreed that it is not. Wayne mentioned that NFPA 20 rules for fire pump controllers now are written more clearly than they had been. Because this is clarification, not revision, he feels comfortable applying the later version of this as well.
We went down a side path here for a few minutes. David’s original counter-example to Gil’s point about new definitions informing earlier versions of the Code was the rule requiring circuit labeling that is specific enough to be useful and reliable. Gil said that as a contractor, he used to spread out all equipment instructions on the kitchen counter, and make notes for a circuit directory on the cardboard box that the loadcenter came in. At night, he’d take this home and type up a directory. (Tony came in for some chiding from the floor over the inadequate space manufacturers provide for circuit identification.)
Pete interrupted, saying that this was the practice of an older generation. Nowadays, the cardboard would be ripped up, and installation instructions trashed. Gil countered that in his experience sitting on the board of the local vocational school over the last three years the kids have been topnotch, engaged. What a difference. This is true in all three classes (years). Previously he found only two or three interested kids to a class, with the rest of the students very disappointing to a committed instructor. Pete commented that this latter, frustrating case has represented his experience in various teaching contexts. Gil noted that he knows of one large contractor who keeps a behavioral scientist on retainer to get employees socialized to act the way they should be expected to.
Someone made a crack about circuit directories in foreign languages. Gil responded that the New York City code explicitly states that they must be in English–not that there’s anything wrong with adding information in additional languages.
Bonding and grounding came next, with a reminded of the difference between the two, and a note about the new definition of “neutral.” Pete asked the reason for the resistance to adopting into Code a standard color code for ungrounded conductors. Gil said that such a standard was removed quite a while back--from the 1964 Code--because there were somewhat differing systems in actual use at the time. Also, it doesn’t account for larger conductors that commonly are sold simply in black. Besides coloring, tagging with numbers or letters is a reasonable option. However, whatever the system, it needs to be posted at each panelboard.
Wayne saw every benefit to requiring a consistent system of identifying all conductors by system and phase not only in feeders, as now required by Section 212.15(C), but also in branch circuits. Gil pointed out a disadvantage: should this become Code, if you discover that the loads are imbalanced, and want to swap some circuits between phases, you would have to change the conductor colors.
We next talked about grounding electrodes and grounding electrode conductors. Wayne, like many of us, never has seen an actual installation using a chemical electrode. Pete has installed some of these for data centers that specified ground resistance of less than one ohm, but has never been asked to come back to replenish the electrodes’ depleted chemicals. Wayne knows of some that have monitors which will notify you as the electrodes’ resistance rises. Gil mentioned that cellular phone towers include such maintenance as part of their standard operating procedure.
John took over now, to talk about the UL White Book and product standards. He pointed out Flexible Lighting Products, which are found on Page 160 of the 2008 volume. It says that they are not intended to be relamped, field-modified, or permanently mounted. An important distinction needs to be made between these and decorative lighting strings, the holiday lights intended for temporary use--not to exceed 90 days.
The idea of not being designed for permanent mounting means that you are not supposed to take Flexible Lighting Products apart to screw them in place, similar to Relocatable Power Taps (which actually were discussed a bit later). The latter used to be known as “Temporary” but “Relocatable” was a preferred term–to clarify that they are not suitable for use on construction sites along with other temporary power uses. Their keyhole openings mean that they remain capable of being lifted and moved. Incidentally, while they might contain surge arrestors, unless they are labeled as transient voltage surge suppressors and specify the protection they offer in terms of the voltage level, they have not been investigated for any protection of this sort. What one of these is investigated for is having the size of conductors and other components corresponding to the rating of the receptacles it contains, so that a Listed Relocatable Power Tap won’t be dangerously overloaded by equipment designed with plugs fitting its receptacles. Wayne noted that this type of product used to ignite when its Metal Oxide Varistor(s) died. John agreed, and mentioned that solid-state equipment tends to suffer “avalanche breakdown.” He noted that nowadays they meet one new requirement, to withstand a certain number of surges; and another, to have a safe end-of-life mode.
John noted that he had some trouble recalling the category applying to “flexible lighting products.” He pointed out that if you access it online, you find one improvement over using the index to the printed White Book: word-search capability. The 2008 White Book is cross-referenced to both the 2008 and the 2005 versions of the NEC.
The issue of tamper-resistant receptacles came up as we were given the opportunity to examine some unusual receptacle covers. These were designed to give a standard duplex receptacle an appearance closer to a decora receptacle, in part by sitting in front of its two faces. The problem with this is that attachment plugs need to fit into a receptacle far enough to make adequate contact, and this restricts covers from blocking more than 1 mm. of their length from entering. Part of the history of this, it turns out, has to do with the holes traditionally found toward the ends of flat plug blades. These used to mate with dimples inside the corresponding spring metal blades inside receptacles, to ensure positive contact. Metallurgical developments made these unnecessary, so the requirement for inserting full blade length to match them up has been supplanted by functional tests. Nonetheless, UL was uncomfortable with listing such covers. Similarly, to date no covers (as opposed to receptacles) have been brought to UL that satisfied all the requirements for tamper-resistance.
The question of tamper-resistant IG and clock receptacles was raised; our presenters were not aware of any being available. Gil noted that there are listed poke-through floor fittings whose covers block the receptacles’ fronts to protect them. The reason these carry the UL label is that each of these is investigated as a unit–box, receptacle, and cover.
Next Wayne brought up a concern about listed equipment whose installation, to his mind, clearly violates the NEC. He takes issue with panelboards that contain breakers for both normal sources and standby or emergency sources, with no separation. In case of fire, he fears, connection to both is likely to be lost. Richard Panizari has come up against this concern of Wayne’s–and Wayne’s the man who gets to say yea or nay. Gil kept arguing that the breakers in these units, at least those that serve the alternate sources, are not disconnects but isolating switches, and therefore exempt from the requirement for separation.
We moved on to a discussion of bonds, grounds, and neutrals. We agreed that bonding conductors, like grounding electrode conductors, can be bare–or covered with insulation of any color. Gil reminded us that grounded conductors of corner-grounded systems are not neutrals.
Gil helped confirm an interesting point for Wayne: supplementary overcurrent devices do not have to be considered in selective coordination. His perspective is that essentially they are part of the equipment.
During the course of the evening Wayne, notably, identified a number of violations in the IAEI Archives pictures used to illustrate the talk: violations that were not at all what the pictures were intended to illustrate. Our presenters acknowledged that this happens often.
We moved on to Section 240.86(A), where Gil noted that one aspect often is overlooked: using series-rated protective systems whose combinations are selected under engineering supervision, rather than by the manufacturer, is permitted only in existing installations.
On we went to the unfolding of another set of rules from 1999 forward: the need for two entrances, and for panic hardware, in electric rooms. Pete commented that at one point, “sharpies” would install 800 amp and 1200 amp equipment side by side, so as not to have 1200 amp equipment and trigger the rule. Wayne noted that panic hardware is cheap, so what’s the big deal? Gil responded that the problem is door swing. Replacing a door is not so simple, when it opens into a corridor needed for evacuation, one that doesn’t have room to accommodate the door’s swing out.
We had a comment on Labor being the source for a couple of rules. Some rumbling was heard in response, but Gil said they had documented “bodies”; the CMP examined the cases and found them legitimate. One is the internal all-conductor disconnects for two-ended fluorescents. Here Wayne, surprisingly, chimed in with support. He’s not known as a softie, but in this case he agreed: it’s worth the trouble to kill all power. He spent time in a coronary care unit, he said, due to getting hung up between some badly cut BX and a ground; he commented with a smile that hitting the concrete may be what restarted his heart.
We were coming to the end of John and Gil’s slides now, and the patient audience was getting a bit restive. A question came up about wiring channels, now that Lighting and Appliance panels are no more. Tony said that in going from 40 to 60 circuit loadcenters, the wireway widths are extending from 20" to 28. Wayne gave Tony another nudge by commenting that jobs tend to sit on hold for some time waiting for engineers to come up with selective coordination designs, and they tend to end up with fuses.
With the last slide, we applauded our presenters, and Jim made some noises about a business meeting. However, most of us were getting up to leave.
That was it for the evening, which wrapped up very shortly before 10 PM. Fortunately, the IO-required treasurer’s report was handled by a list printed as part of the distributed agenda. Jim made noises about calling a special meeting of the executive board to address other business items.
NEW FEATURE! Boy, we learn a lot at the annual Code Workshops
put on by IAEI’s Sections! At the Eastern Section, one
benefit everyone who shows up on time gets is chewing over a
half-dozen or so Codes and Standards questions each morning over
breakfast. What I think is, why should you miss out on this fun
and learning? Here are a first few questions for you to ponder.
Look for more in future mailings. At each meeting, I’ll
pass out (my understanding of) the answers that the group of
mavens came up with at the Code breakfasts. For those questions
whose answers may differ depending on which jurisdiction you’re
working in, I’ll talk about at least the 2005 as well as
the 2008 NEC. The answers also go on our web site, eventually, in
the meeting’s minutes. For some Code questions, just as for
some that come up in the field, you may need to go online, or
look in your White Book, as well as into your NEC.
These first few are chosen with our host-and our November presenters--in mind.
1) GFPE: Articles 426 and 427 talk of providing not
GFCI but GFPE for protection of snow/ice/pipeline/vessel heating
equipment. Suppose the customer has an oddball panel, and they’re
watching their pennies. They don’t want to replace the
panel-preferably not even install a subpanel. You go to the
distributor: can one find CBs manufactured nowadays offering GFPE
that are legitimately Classified for use in other manufacturers’
Answer: Yes, potentially. Many have been submitted for such classification and failed their tests. All major manufacturers’ web sites will tell you where their CB s are Classified.
2) AFCIs: Installing AFCIs on lots of circuits may add a whole lot of unnecessarily long leads running from them to the neutral bar or, contrarily, having to bring circuits’ return conductors a lot further into a panel than you have needed to in the past. Given this, is there any issue with shortening or splicing extensions on to the neutral leads of AFCI or GFCI or switched-neutral CBs? Also, AFCIs run a little warm; is this panelboard going to overheat?
5) If properly installed, they may run warmer than standard CBs, but they and it and the wiring will stay well within design parameters. What's more, it's perfectly legal for you to trim any excess wire from those leads.
3) Too Clever? Underground Schedule 80, NMRC, is damaged. The electrician wants to pull back the wires and, rather than glue on a regular coupling to add the extension, glue on an expansion coupling (to be buried when the floor is patched); he believes this fitting will make the repair easier. If he buys this instead, will he end up p’ed off because the inspector has to reject the work, or is this use in keeping with the Listing of an expansion fitting?
No violation. The Listing of expansion fittings says nothing to restrict this use.
This is the report of the meeting of the George Washington Chapter on Tuesday, September 16, 2008. Attendees included six associate members, six inspector members, one visiting contractor, and three allied professionals--our presenter and two associates.
At 6:38, Jim called the meeting to order and prayed. Then we got to business.
Wayne Robinson has arranged for the hospitality of Prince George's County for quite some time now, and has faced rather a struggle to do so. Tonight, despite his having reserved the meeting room for us with plenty of notice, he had to evict a different group's meeting in order to accommodate ours. He is giving up this battle.
As of this writing, we're homeless. However, Ed Holt volunteered to contact PEPCO, in the hope that we can secure the use of their meeting facility in Forestville. (N.B. See "Next Local Meeting," above, for the actual new location.)
Since it was announced, a total of eight people showed commitment to Wayne's rescheduled "2008 NEC Changes" seminar. Thud. Wayne was philosophical about this, commenting on the number of such seminars already offered by various organizations.
The one other seminar that has been talked about seriously was the Master's Exam preparation which Pete Bowers volunteered to teach, sponsored in conjunction with the IEC, at their location.
No formal financial report was requested or presented, but David mentioned that our kitty is in bad shape. Hope flowers, though. In the past, seminars served as the primary source of money for our budget. The few dollars needed to put out mailings are more than covered by the International Office's distribution to the chapter from member dues. Besides, nowadays the cost of member notifications generally is very modest, thanks to most members' agreeing to accept email notification. However, the IO disbursement dollars are nothing like what is needed to pay for representation at Section meetings. The chapter's tradition is to cover the out-of-pocket expenses: registration, lodging (which category includes meals), and where far away, travel. Presenting any seminar, at least without importing paid speakers, carries the likelihood that we will be able to partly restore the bank account.
The last main item of business addressed before the technical presentation was an update on the Safety Smart children's program. It has taken a long time to get to this part of IAEI's purpose. The kit was ordered the day after the meeting. It arrived quickly, and as soon as training can be completed, Pete and David will look to start teaching Middle Schoolers. Because Underwriters Laboratories, Inc. no longer is underwriting part of the cost, the kit is rather more expensive than expected, but Pete and David will kick in the shortfall beyond what was authorized. Once we've taught a number of classes--90 children--supplies also will need to be replenished. Wayne volunteered to cover the next supply order out of his pocket.
In one other matter, Shirley asked the status of D.C.'s electrical inspectors. David reported, based on what he had read, that the general housing inspectors had been fired for not passing the ICC tests. Pete added the information Shirley sought (which David had not known, despite sharing Pete's distinction of being a DCRA-approved third-party inspector): Pete reported that all but two of the District's electrical inspectors are gone as well.
Kerinia Cusick. M.E. (Senior Executive, Huthwaite PR), representing the Solar Energy Industry Association (SEIA) in our area, promised us a mini-seminar on inspecting photovoltaic installations. While a talk outline was promised, and a biography of the presenter, the well-known expert who had planned to teach us was called out of the country on urgent family business, so it was just as well that no such materials had been posted on our web site. Regardless of this, Kerinia had assured us of a valuable presentation, and this most certainly is what we received.
Bill Poulin, Director of Products and Services for BP Solar--yes, the entire shebang--has been with BP Solar and their predecessor for 29 years. He came down all the way from Frederick, Maryland to spend the evening with us. And we kept him a good, long time. What's more, Peter Lowenthal, Executive Director of the local SEIA group, who has been part of it for 20 years, joined us for the evening, and offered his knowledge as appropriate.
Even before Bill began enriching our technical education, Peter dangled additional training opportunities before us--"us" meaning any members who so choose. As details become available they will be posted at http://www.mdv-seia.org/events.html .
Since Bill's talk was oriented largely around BP's product and the NEC, Peter offered some additional perspective on what is available locally. Sun Edison is also active in our area, selling not PV equipment or even installations, but rather the power derived from PV equipment. They negotiate this in contracts with a property-owner, when they find a commercial customer with enough roof footage to make it worth their while. They install the equipment on customers' buildings, charging nothing for the installation, retaining ownership of it, and merely selling its output. An intriguing concept, concerning which it would have been fun to learn a great deal more.
Peter also talked about the support that Maryland's present
governor provides for alternate energy programs. Sun Edison's
rooftops program hinges on the tax credits to make it
economically rewarding. Bill added that not just anybody can
apply for Maryland's state energy incentive grants: the signature
of a licensed electrician is needed for the grant to be
Later in the evening, to continue on the theme of practical economics, we were assured that the price of modules is likely to resume its pattern of dropping over time, after having leveled out due to a temporary shortage of the refined silicon material needed for the crystalline-type diodes.
Bill started his technical presentation by emphasizing that PV
panels, if not the rest of the systems, are expected to last 25
years and longer. That's 25 years of supplying up to 600 Volts
DC, with much of the equipment and wiring system continually
exposed to the outdoors. Moreover, Article 690 is dealing with an
item that is putting out voltage all the time when sunlight hits
it. He reported that his company has a contract with the Home
Depot chain, and they have fired more dealers, for reasons such
as safety violations, than they have retained.
(Despite this, Wayne still reported that he has observed pretty bad systems coming out of PV installers working out of Home Depots.)
Bill contrasted ANSI/UL 1703, the U.S. standard covering solar panels, and IEC standards 61215 and 61730, the International Electrotechnical Commission standards. UL 1703 covers safety. It may test a panel to destruction, and if throughout this the panel (or other component) doesn't pose a hazard, it can pass. It is not required to function by the end of the testing. The IEC standards, in contrast, add in performance requirements. At this point David expressed concern about the validity of the certification process when the IEC standards are employed. Bill clarified the difference between two European markings,those associated with IEC and CE standards. Furthermore, he took this opportunity to inform us that while the European CE standards used to allow manufacturers to self-certify compliance, he believes that at some point in 2008 a requirement for third-party certification was added. Subsequently, at the meeting of the American Council on Electrical Safety (ACES) hosted this year at the IAEI Southern Section's Annual Meeting, this appears to have been contradicted. In fact, the European Commission has requested--in an agreement signed on our end by George W. Bush in April 2007, that OSHA accept a manufacturer's statement, a Supplier Declaration of Conformity (SDoC), represented by the CE mark, as a substitute for testing by a Nationally Recognized Testing Laboratory. Further information is available at the site where OSHA published the request that the public supply evidence-supported arguments favoring or opposing this move. The site gives ample background too, discussing the present status of the European model, as of late October, 2008. The Comment Period will close on Tuesday, January 20.
Now Bill moved on to inverters. The standard applicable to them is UL 1741. One critical requirement is provision of an anti-islanding feature, which guaranteesthat they will not backfeed into a utility system that is down. All inverter units manufactured by the reputable companies are designed to handily exceed all utility requirements in this regard. When the inverters' circuits are restored after having been have been disconnected for whatever reason, they will self-start, taking a period of four or five minutes. It takes them this long to synch tightly to the utility frequency and voltage--within the tight limits to which they are designed to hold. An inverter, whether single- or three-phase, actually is designed to put out slightly higher voltage than it senses from the utility, so as to be able to feed power into the utility system and run the customer's meter backwards, as intended.
You may detect from this that Dave is quite an engaging speaker; moreover he's one with 19 years' product and Code experience under his belt to give plenty of clout to the information.
"When asked, I've been assuring members that this is just administrivia, enabling our representatives to move the organizational registration to where you'd prefer it, down where the IO is actually located. I don't know whether there are particular problems with having it registered elsewhere, but don't know of any reason for people to think twice about the proxy. Is there anything else I should know, and communicate?"