National Electrical Installation Standards

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Revision of NECA 121-201X, Standard for Installing Nonmetallic-Sheathed Cable (Type NM-B)and Underground and Branch Circuit Cable (TypeUF)

Revision of NECA 303-201X, Standard for Installing and Maintaining Closed-Circuit Television (CCTV) Systems


Revision of NECA 413-201X, Standard for Installing and Maintaining Electric Vehicle Supply Equipment (EVSE)



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Featured Standards


NECA 416-2016 Recommended Practice for Installing Energy Storage Systems

This standard describes methods and procedures used for installing multiple types energy storage systems. It also includes information about controlling and managing energy storage systems, in addition to commissioning and maintaining energy storage systems.
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NECA/FOA 301-2016 Standard for Installing and Testing Fiber Optics

This standard describes installation and test procedures for fiber optic cabling networks. This standard applies fiber optic cabling installed indoors (premises installations) and outside plant (OSP) applications.
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Find the major provisions of electrical code, enforcement, and contractor/electrician licensing requirements for each state in the U.S.

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Code Question of the Daytextbook

  • Tuesday, October 17, 2017
    CQD: 10/17/2017

    Re: CQD answer published Tuesday, October 10, 2017 - Generator Grounding 2

    Connecting a generator utilizing a pole to switch the neutral (grounded conductor), and grounding the generator's neutral at a remote generator, does in most cases cause a high risk of parallel path ground loops. Unless the generator's ATS switches the complete building, then there are two separate ground electrode systems which come into play when the ATS switches to the generator.

    In the LA area, one such connected system completely took out the very Emergency Broadcasting System the generator was supposed to protect.  A very difficult to find problem, this was due to stray ground (Earth) loop currents over communication coax cable shielding caused by Earth-currents between the two electrode systems.  Eliminating the use of the grounded conductor pole in the ATS, and bonding the generator's grounded conductor on the same electrode system as the building's service solved this "ghost" problem.

    Scott Cline

  • Monday, October 16, 2017
    CQD: 10/16/2017
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