National Electrical Installation Standards

Standards as High as Your Own

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  • December 28, 2018

    Rephrasing my earlier question. I think I have always called a receptacle an outlet. But apparently an outlet is a place that receives electricity, right? So that means that a ceiling light is an outlet and therefore covers the "there must be a switched outlet in each room" part of the code? Debbie Olsen
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  • December 27, 2018

    Re: CQD answer published November 29 and December 18, 2018 - 1) Hi Charlie, Thanks for your work, I have not submitted in quite a while. By wrapping the grounding conductor around the raceway you will create a choke effect much like the old BX cable that used the spiral metal jacket as a grounding means. A thin uninsulated metal ribbon is installed inside the raceway to shunt the spiral coils and defeat the choke coil effect. Rick Munch CMP 1 2005 2) I just want to say that I was very impressed with Jennifer's question regarding running the bonding conductor straight vs a spiral type of installation. Rich Van Wert
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  • December 26, 2018

    I have been following NEC Code question for a long time, first heard from my first electrical class. 22years later I was wondering. as a Master Elec. And contractor. I have recently Noticed (2017-2018) many related Home owner/handy man Questions. Normally you would respond, Electrical work should be done by LICESENED ELECTRICIANS. Though, I can't seem to find that. Should Any Electrical Work Be Performed Buy Home Owners and Handyman, adding switches, plugs, ceiling fans. Your thoughts, Matthew C Geres
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  • December 21, 2018

    I have a 240 volt 2 # 6thhn + # 10 gr (3 wire) no neutral hot tub. The hot tub is fed from a spa gfci 60 amp disconnect. The spa 60amp disconnect is fed from the main pnl with 2 # 6 thhn + a 10 gr can I use a # 10 neutral since it is only used on the spa neutral bar so the neutral off the gfci breaker can tie into the main pnl neutral and the gfci breaker will function correctly Don Sieber
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  • December 20, 2018

    When installing a 400A 240/120V service at a dwelling, service entrance conductors are 3/0 Cu paralleled from meter enclosure to service disconnecting means, 1 panel with 200A and 1 adjacent 200A fused service disconnect (connected by trough and bonded), the electrode grounding conductor to 2 ground rods (6' apart) and to the nearest building water lines using #2 Cu (Hot/cold/hot re-circulation and boiler zone lines all boded by same conductor) is it permissible to run the auxiliary ground from each service disconnecting means (2) with #4 cu from each if irreversibly connect to the #2 Cu equipment grounding conductor connected to the grounding electrode? {Note: the 2nd Service disconnecting means feeds a dislocated 200A sub-panel elsewhere in the dwelling with 4/0 SER Al.} Thank you. Roger Miller
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  • December 19, 2018

    I have a ungrounded GFI outside that I just can't ground, is that violating and CODE? I live in Bolingbrook IL. Scott Johnson
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  • December 18, 2018

    Good Morning, I begin my mornings with your questions and answers, which is very informative and a great learning experience. In a portion of NJ where there are multiple electric utility providers, we have a situation, which is not unique to the entire State but where this Utility exists it’s now become an issue. They have begun to require a Disconnecting means ahead of the meter for any 277/480V services and/or CT cabinet for “Cold Sequence” so they may work on their equipment without having to shut down transformers or disconnect the service. As an electrical inspector and a member of the Code Advisory board in NJ, my interpretation of 230.82 is that this is considered a “Meter Disconnect” not service equipment, therefore no grounding is done in this enclosure and after the installation the disconnect will be locked by the Utility. In our state we are not allowed by this particular Utility to install the GEC in either the meter enclosure or CT cabinet. My interpretation also is this “Disconnect” must have the appropriate AIC rating which would be provided by the utility, and here lies the issue. I’m not aware of any non-fused disconnect which has an AIC rating of more than 10,000, therefore most times, it must contain OCP either with fuses or a CB to meet the available AIC as per the utility. Some members of our committee believe since there is overcurrent protection in this enclosure, this is considered the “service disconnect” and the GEC must be brought to this enclosure. My contention is as per 230.82 it is not, and the “Service Disconnect” will be on the load side of this “Meter Switch”, in which ever configuration it may be. Switch gear is generally not an issue since most manufactures will construct the switchgear with the “Service Disconnect” ahead of the CT compartment and the compartment with the branches. Again in switchgear the ability to install the GEC is easy since the Neutral bar extends into the branch cabinet. Your comments please and thank you for your time. THANK YOU, CARL GURNEY
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  • December 17, 2018

    Re: CQD answer published Thursday, November 29, 2018 -External Equipment Bonding Jumper Hi Charlie, The answer you gave about the external bonding jumper not having to be run straight with the liquid tight flex doesn't appear to match the code words "routed with the raceway". Wrapping the bonding jumper around the flex would not be following the raceway or the wires inside Thank you, Jennifer
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  • December 14, 2018

    Does NEC code applied to vehicle electrical systems, specially when vehicle has 120VAC outlet? Miah Baset
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  • December 13, 2018

    Charlie, Why is the size in mm for a 2/0 bare conductor different in the first column of Table 8 in Chapter 9 than the column for overall size? I never noticed before because I usually look for the inches and not metric. Thank you, Claudia
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  • December 12, 2018

    Re: CQD answer published Friday, November 30, 2018 -Pool Eq GFCI Protection Gentlemen: I remember Charlie and used to have many conversations with him at IAEI functions over the last 25+ years. We miss him. I am an avid reader of Code question and would like to offer a possible correction to your answer of Thursday, Nov 29, 2018. My understanding of Article 680.23(A)(3) is that an underwater luminaire for a pool must have GFCI protection “in the branch circuit” and that’s the way I’ve been teaching it in my classes. This is different that what is called out for other equipment like the pool cover, pump motors, etc. If the feeder for the panel is GFCI protected it would require an additional GFCI device in the “branch circuit” for the underwater luminaire even if the branch circuit originated from a panel that was protected by a GFCI Main. Thanks for the fine job you are doing for the industry. George Little 2) Good morning. Please correct me if I’m wrong, But in regards to the answer given concerning the GFCI protection for pool equipment being located in the feeder for a pool sub panel. If there are underwater Luminaires installed you must pay attention to 680.23(A)(3). Gfci protection for luminaires must be located in the branch circuit. Barry Wilbur
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  • December 11, 2018

    Charlie, The 2017 NEC code reference at 501.15(C)(3) for sealing and drainage of Class I, Division 1 and 2 installations tells the user of the Code that the thickness of the sealing compound installed in completed seals, other than listed cable sealing fittings, shall not be less than the metric designator (trade size) of the sealing fitting expressed in the units of measurement employed; however, in no case shall the thickness of the compound be less than 16 mm (5∕8 in.). This language seems to be telling the installer and inspector that for a 19 mm (¾ in) seal off fitting the sealing compound shall be ¾” but in no case less than 5/8 in. Therefore, is a 5/8 in. installation of sealing compound meet the intent of this code requirement? If not, can you explain the intent of this language? Adolphe Menjou
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  • December 10, 2018

    Re: CQD answer published Tuesday, November 27, 2018 - Good morning, Your answer to yesterday's question was quite factual. The problem is, you failed to answer the question completely. The exception to 680.25 that was present in the 2011 NEC was removed through the process but was inadvertently not removed from the text of the 2014 first printing. It was however noted in the Errata No.: 70-14-2, items 31 and 32. It would not have been present in subsequent printings. We try really hard to get stuff right, but we're still human! Now, if we could only get every area of our great land on to the current, 2017 NEC, what a victory for electrical safety that would be! Thanks for trying hard every day to provide us with answers to our questions. Grant Hammett
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  • December 7, 2018

    When installing conduit pipe into a wall strut does the clamp holding the conduit have to have a certain strength? the clamps are very thick steel and I am wondering if there is a load weight or strength requirement. Hope this makes sense. Jeffrey Kintzler
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  • December 6, 2018

    Question 1) does pvc underground conduit need to be spaced apart. If it does what is the code article. 2) what is the meaning of 310.15(3)(b) Jim Churilla
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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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