Questions about Scope of NEC

[jaggedben]

551.1 only says that Article 551 does not cover low voltage and automotive circuits and their extensions. Does this mean that the automotive circuits (such as the dashboard, drivetrain components, and exterior lights for automotive purposes) of the RV still have to follow the requirements of all other articles, and that the NEC still applies to RVs that only have low voltage and automotive circuits?

No, because 90.2 says automotive vehicles other than mobile homes and recreational vehicles are not covered by the NEC. So if it's part of the automotive construction that isn't covered in the Articles on mobile homes or RVs, then it's not covered by the NEC.

Also what would be the enforcement mechanism? You don't need a building permit to buy an RV. It wouldn't surprise me if the on-vehicle parts of Art 551 are largely ignored just because in many places there may be no laws that require it to be enforced.

Also, is an RV that can only run 120V circuits via an inverter from its batteries charged via mains power (with no way to bypass the battery to connect its internal circuits to the mains directly, like power receptacles on an EV) not covered by Article 551?

Some sections seem to apply, for example 551.42 refers to 'each RV containing an ac electrical system'. Again though, depends on adoption and enforcement.

Anyway, thank you very much for mentioning this article to me. I could see that a motorhome is considered an RV by the NEC because it is listed under here.

Also check out the definitions of an RV and mobile home in their respective articles.

 

[00crashtest]

No, because 90.2 says automotive vehicles other than mobile homes and recreational vehicles are not covered by the NEC. So if it's part of the automotive construction that isn't covered in the Articles on mobile homes or RVs, then it's not covered by the NEC.

Also what would be the enforcement mechanism? You don't need a building permit to buy an RV. It wouldn't surprise me if the on-vehicle parts of Art 551 are largely ignored just because in many places there may be no laws that require it to be enforced.



Some sections seem to apply, for example 551.42 refers to 'each RV containing an ac electrical system'. Again though, depends on adoption and enforcement.



Also check out the definitions of an RV and mobile home in their respective articles.

I never knew they would consider only the electrical components that make a road vehicle an RV. I thought the scope outside of Article 551 would apply to all parts of the RV, since the automotive components are also part of the vehicle as a whole. Where do you see that the automotive compenents of an RV do not apply at all to the NEC, not just for Article 551?

 

[00crashtest]

Look in RCW 19.29 and WAC 296-46B

I just checked RCW 19.29 and it doesn't give much info. However, WAC 296-46B gives the full code and it is way more specific than the NEC. It also specifies that that code and RCW 19.29 shall prevail when either of them contradict with the NEC. In the Wiring and protection—Grounding and bonding article for example it specifically states, "Except for mobile/manufactured homes, a concrete encased grounding electrode must be installed and used at each new building or structure that is built upon a permanent concrete foundation." This immediately and clearly rules out all types of grounding electrodes that are not encased in concrete, when though the NEC (all versions AFAIK) allows them.

 

[romex jockey]

Who is asking and what are you referring to?

any NEC user, regardless of obligation to it Tom
~S~