National Electrical Installation Standards

Standards as High as Your Own

The National Electrical Code is the bedrock of the electrical construction business.

Do you know all the ins and outs of the Code? NECA and Electrical Contractor magazine are pleased to present their daily online feature, “Code Question of the Day,” Sponsored by Eaton.

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    Thursday, December 5, 2019


    Re: CQD answer published Wednesday, November 27, 2019 - 2020 NEC Emergency Disconnects

    1) AGREE with KEN.. it’s a Stupid idea some engineer came up with brought it to other engineers and over thought the process and added it to the 2020 code. WE ALL Still have time to voice out public objections on the 2020 NEC Bill Schell

    2) "The concerns you express about burglary and mischief can be dealt with by locating the disconnecting means outside and locking it in the on position but locating the panelboard inside the building. The really evil people will find a way to defeat everything. The benefit to having the disconnecting means outside is for emergency responders so they can deenergize the interior wiring before entering the building." If it's locked in the on position, how do 1st responders deenergize it? Dave

    3) Thanks for all your hardwork keeping us all on track. The poster that responded to the Nov 8 discussion on placing of breaker boxes on the exterior may be failing to understand what I believe to be the best reason to do so. The main breaker being accessible from the exterior favors when the fire department is dispatched to the building. First thing they do is to shut power down for safety reasons that I don't think needs to be explained. As you said, those "bad guys" will access a panel if they are in or outside the building if there intent is to disconnect security. Happy Thanksgiving to all! Jeff Frishof
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    Wednesday, December 4, 2019


    Re: CQD answer published Monday, November 25, 2019 -Warning Ribbon for Underground Service Conductors

    Question regarding the Warning tape over HDPE. We are on a project now. They are doing horizontal boring to install feeders to carports that supply the AC to inverters. With horizontal boring there is no way to install warning tape. How is this addressed? It there an exception?

    Vern Detweiler




    Hey Vern thanks for your follow up question. There is not an exception to 300.5(D)(3) but the rule only requires a warning ribbon to be places in a trench for directly buried underground service conductors, not as in your case for feeders. Also, for directional boring there is no trench.

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.

NECA STANDARDS: NECA publishes the National Electrical Installation Standards™ (NEIS™), a series of ANSI-approved performance and quality standards for electrical construction. Visit for more information. NEISÔ can be purchased in three formats: as paper books, on CD, or as electronic downloads.

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