National Electrical Installation Standards

Standards as High as Your Own

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  • June 27, 2017

    Morning! I had a customer call and ask if our products are NEC code certified/ up to code? We provide security cages that go over electrical boxes - they all have access doors to provide full access to box- What exactly does he need to know? Is there a rule for this? Marissa Osborne
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  • June 26, 2017

    Charlie, Until the NEC is written in English, I have another question for you. I have three scenarios: 1) New construction with copper water service, concrete footing re-rod ground; 2) New construction with plastic water service, concrete footing re-rod ground; 3) Old construction with copper water service and no concrete footing re-rod ground. For 1), 2), 3), are ground rods required and, if 25 ohm resistance is not confirmed, is a second ground rod required? I would contribute to a fund to pay a good technical writer to re-write the NEC so any two readers can come to the same conclusion. Of course, you would be out of a job. Dave
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  • June 23, 2017

    Re: CQD answer published Wednesday, June 14, 2017 - Would you answer still be the same for NEC 2014 for same condition? I am asking on behalf of a friend so he can read this. New York is still under the 2014 NEC. Bill Schell
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  • June 22, 2017

    Mr. Trout: Seems many inspectors disagree on this code section: Permitted use of cords 400.10, 400.12. What is your opinion? Can a flexible rubber power cord provided as part of a condensate pump be allowed above a drop ceiling? Also, what about it use in a drop ceiling used for environmental air (aka: plenum)? Thanks, Alan Chech
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  • June 21, 2017

    Hi, on the 2011 NEC Chapter 9, Table 1 Percent of Cross Section of Conduit and Tubing for Conductors, it gives 53 % for 1 conductor, 31% for 2 conductors, and 40% for over 2 conductors. It means that the percentage is increased when there are more than 2 conductors. Please, can you explain the reasoning behind those values? Thank you for your everyday help and for spreading your knowledge. Marco Perez
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  • June 20, 2017

    I have an I-line panelboard with a 70 amp feeder breaker. I am running 125' to a control panel for multple motor control. Do I need over-current protection at the panel for the protection of the feeder conductors? Mike Kutter
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  • June 19, 2017

    Is a surface mounted raceway (6x6) allowed above a 42 circuit 120/208 panel in place of bending 90's for the branch circuit conduits? John Hopkins
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  • June 16, 2017

    Mr. Trout: Seems many inspectors disagree on this code section: Permitted use of cords 400.10, 400.12. What is your opinion? Can a flexible rubber power cord provided as part of a condensate pump be allowed above a drop ceiling? Also, what about it use in a drop ceiling used for environmental air (aka: plenum)? Thanks, Alan Chech
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  • June 15, 2017

    Re: CQD answer published Wednesday, June 7, 2017 -Wall Space 1. Bless all of you for continuing this feature! Referencing answer published 06/07/2017: The answer addressed properly the countertop receptacle outlet rules. I feel the question was not related to that issue. Very often a kitchen island or countertop peninsula also serves as a room divider. The kitchen is on one side and a dining or living room area is on the other. When that occurs the non-kitchen side is indeed wall space for that room. This is as described by 210.52(A)(2)(3). So the wall-spacing at 210.52(A)(1) will apply. When there is no receptacle there, it will require use of an extension cord to power the TV, stereo system, or computer desk that we often see in-use at that location. The non-kitchen side of the peninsula counter (less-often an island) is commonly used just like any other wall by the dwelling tenants. It needs a receptacle outlet. Carry-on, you are doing a great job! Scott Davis 2. Hello, I’ve read your response to Stefan Hamran, dated 6/7/2017, related to kitchen island and/or peninsula wall space receptacles. I believe Stefan’s question is if the back of the kitchen island or peninsula is considered as wall space as defined under 210.52(A)(2) and therefor requiring additional receptacles along the back of the cabinets at the floor line to meet the spacing requirements of 210.52 (1). Are receptacles at the floor line required on the back of kitchen islands and peninsulas? Mark A. Prendable 3. Good morning, Keep up with a good work. Can you please further clarify if the peninsular section (facing outside wall of the kitchen) is considered a wall space divider as per 210.52(A)(2)(3)? If above is yes, and peninsular section is next to any room that falls to section of 210.52(A), such as typically is next to living room, then this wall space of peninsular would need additional general requirement receptacles that are connected to living room circuit. Regards, Alban Berani
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  • June 14, 2017

    Are Photo-voltaic arrays allowed to be interconnected to emergency generators under NEC 700? My question concerns a 500 KW generator in a larger middle school. Greg Evers
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  • June 13, 2017

    In a residential application where the disposal is located under the kitchen sink in a cabinet, is gfci protection required in the 2017 NEC? Stephen
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  • June 12, 2017

    Charlie, While the rules in 250.122(F) do not contain the words "fully sized" the rules for multiple raceways and cables not installed in raceways or cable trays require that the EGC in each raceway of cable be sized based on the rating of the OCPD and Table 250.122, the effect is that the code requires a fully sized EGC in those cases. Don Ganiere
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  • June 9, 2017

    Good morning, I enjoy starting my day with the CQD. We have a discussion going on here at the office with differing opinions. It is my understanding “fuse reducers” that will allow for example, a 40A fuse to be installed in a 30A Fused Disconnect Switch of the same voltage are illegal; however, I am unable to find the code section to support my position. Your help in this matter is greatly appreciated. Larry N. James
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  • June 8, 2017

    Does a 50 amp outside outlet for an RV have to be on a GFI circuit? Thanks Joe O. from Florida
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  • June 7, 2017

    Ever Good morning! I have a question on bonding... We have a 277/480V panel feeding a 112.5 KVA transformer a foot away with FMC and then FMC from the Xfmr to the 120/208V panel a foot away, both sides measure around 4' in length of FMC. We have the correct size EGC in the FMC's bonding the panel can to Xfmr case. Does the supply side of the Xfmr FMC connectors have to have bonding bushings (or just a plastic bushing) on them to satisfy the supply side bonding jumper requirement 250.30(A)(2) or for any other reason? Thanks, Kelly Wofford
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ABOUT CQD: NECA’s Code Question of the Day (CQD) is a leading National Electrical Code® forum for NECA and the industry. The CQD generates a lively dialogue and relative practical and Code-based responses to an ever-increasing and interactive audience.

IMPORTANT NOTICE: All answers are based on the latest edition of the National Electrical Code®, unless the question requests a response based on a specific edition. This correspondence is not a formal interpretation of the NEC®. Any responses expressed to the questions are opinions and do not necessarily represent the official position of NECA, NFPA, or any technical committee. In addition, this correspondence is neither intended, nor should it be relied upon, to provide professional consultation or services.

ABOUT CHARLIE: Charles M. Trout, better known as Charlie, was a nationally known NEC® expert and author. He served on several NEC® technical committees and is past chairman of CMP-12. In 2006 Charlie was awarded the prestigious Coggeshall Award for outstanding contributions to the electrical contracting industry, codes and standards development, and technical training. Charlie was also a member of NECA’s Academy of Electrical Contracting. Charlie’s experienced team of industry experts keep the CQD dialogue and discussions active and informative in the spirit of the man himself, as he wanted.

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