National Electrical Installation Standards

Standards as High as Your Own

Tuesday, July 23, 2019


I read code question of the day just about every day. Thanks for this service. I am about assemble light fixtures in a lighting showroom. I will have to install and wire many fixtures. Because these fixtures are for sale and may be removed for new products can this installation be considered temporary? I don't think so because many fixtures will be installed for months or even years. But is their some kind of special provision for relaxation in the NEC for this type of situation? I've looked through Article 590 and I see time constraints. I would like to hear your opinion.

Thanks Dave


Hey Dave thanks for your question and the compliment. It is not clear if the luminaires (formerly called fixtures) will be sold with the "wiring" connected to it. Often outlet boxes are installed for lighting displays in lighting sales areas using wiring methods in NEC Chapter 3. The luminaires can be sold, removed and replaced without needing any temporary wiring. If temporary wiring is desired, the AHJ will need to determine if that is acceptable based on 400.10, 400.12 and the time period. The 90 day time limit in 590.3(B) is for holiday decorative lighting and similar purposes.

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