National Electrical Installation Standards

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Revision of NECA/NEMA 605-201X, Standard for Installing Underground Nonmetallic Utility Duct.

Revision of NECA 305-201X, Standard for Fire Alarm System Job Practices

Revision of NECA 781-201X, Recommended Practice for Installing and Maintaining Lighting Protection Systems

All NEIS Currently Available for Public Review

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.

US Electrical Codes & Regulations by State »
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Building Codes Assistance Project Energy Code Adoption

Code Question of the Daytextbook

  • Friday, July 28, 2017
    CQD: 7/28/2017

    Rule 250.122 (B) says "Where ungrounded conductors are increased in size from the minimum size that has sufficient ampacity for the intended installation, wire-type equipment grounding conductors, where installed, shall be increased in size proportionately...".  What defines "the minimum size"?  For example, (using values for copper from 75° C column of T310.15 (B) (16) and assuming no factoring is required), 600 kcmil is frequently used.  But parallel # 3/0 (167.8 kcmil) could also be used (obviously with paralleled EGCs).  Using this option, is the minimum size to be considered 335.6 kcmil? 

    John Duggan

  • Thursday, July 27, 2017
    CQD: 7/27/2017
    View Question and Answer

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