National Electrical Installation Standards

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Featured Standards


NECA 303-2019 Standard for Installing Closed-Circuit Television Systems (CCTV)

This standard describes installation procedures for new closed-circuit television (CCTV) system equipment installed for video surveillance and for protection of building interiors, building perimeter, and surrounding property.

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NECA 120-2018 Standard for Installing Armored Cable (Type AC) and Type Metal-Clad (MC) Cable

This standard covers the identification, selection and installation of Type AC and Type MC cables, which are used for electrical wiring for residential, commercial and industrial occupancies.

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State Regulationsusa country shape

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

  • Monday, December 4, 2023

    Good morning code enthusiasts, Where cable tray is covered with solid unventilated covers, Section 392.80(A)(1)(b) say that the Ampacity of Multi-Conductor Cables in Cable Trays shall be derated to 95%. The contractor wants to use this type of unventilated cover but make it larger than the tray to allow airflow over the cables, and not use the 95% derating factor.

    Would this be acceptable? I don't see anything in the code allowing the cover to be oversized to avoid the derating factor. If anything, I think this could possibly be a UL listing issue, but the code doesn't seem to permit this. Best. Clive T.

  • Friday, December 1, 2023

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