Installing EVSE next to meter pole, AFTER main breaker, question of code and conventions....

[cdherman]

OK, I have a meter pole that has a meter and a great big 200A disconnect that services the entire property.

I want to pull a 100A rated set of wires off the protected (downstream) side of the 200A breaker, and run them about 18" to a 100A breaker box. From which I will then move on with an EVSE install (Intend to try the Ford unit initially.

The 100A sub breaker will be attached via rigid metal conduit, about 4" from the main box. I think this is code. Since the distance is so short. Technically, the short run of 100A rated wire is "unprotected" since it is attached to a 200A breaker. But I think I read somewhere that with that short a run, in metal conduit, it can be done, so long as it of course terminates at an appropriately sized breaker.

Interestingly the PO wired a whole garage off the 200A breaker, ran wires underground for like 20 feet, and then put a 20A breaker in the garage. I suspect that is NOT code, or entirely bright honestly. But that's not my problem today. Its not the garage that is at risk, but if someone decides to dig a post hole and hits that line, they would get all 200A until something burned clean through........

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[Maquis]

The NEC has what are called “tap rules”. They define how far you can run conductors that are not protected at their source.

What you want to do should comply. The second scenario you describe would be compliant if the 20A breaker is mounted on the outside of the garage.

 

[cdherman]

The NEC has what are called “tap rules”. They define how far you can run conductors that are not protected at their source.

What you want to do should comply. The second scenario you describe would be compliant if the 20A breaker is mounted on the outside of the garage.

Yeah, I've been searching up and down this evening. As long as the feeders are outside of the structure, seems the rules are kind of vague. And then local jurisdictions make some of their own rules too. But basically, if you have an unprotected run of wire, OUTSIDE, of the structure, its pretty much OK to have it unprotected so long as the feed is "reasonable". Some say 5', some less, some more.....

I see another post where "advice about code" gets deleted. Hope that does not occur here. I am certainly not eliciting advice that would be in contradistinction to code. However, knowing code these days is a bit of a rabbit hole.........

 

[Maquis]

Yeah, I've been searching up and down this evening. As long as the feeders are outside of the structure, seems the rules are kind of vague. And then local jurisdictions make some of their own rules too. But basically, if you have an unprotected run of wire, OUTSIDE, of the structure, its pretty much OK to have it unprotected so long as the feed is "reasonable". Some say 5', some less, some more.....

I see another post where "advice about code" gets deleted. Hope that does not occur here. I am certainly not eliciting advice that would be in contradistinction to code. However, knowing code these days is a bit of a rabbit hole.........

The posts that get deleted are those that promote doing things that are obviously dangerous or promote doing things that are NEC violations (such as suicide cords, or backfeeding without an interlock). I don’t think you’re doing that here.

The NEC tap rules for wires that are completely outside of a building are not vague at all - an unlimited length is allowed. I’m not aware of localities that have modified this rule - not saying there aren’t any, though.

The 5’ thing you’re referencing is about service conductors entering a building, not taps. The NEC is vague here and only states that the overcurrent device be located “as near as possible” to where the wires enter the building. Many localities have amended this rule by adding an explicit allowable length, often 5’.

 

[Pioneer74]

Yeah, I've been searching up and down this evening. As long as the feeders are outside of the structure, seems the rules are kind of vague. And then local jurisdictions make some of their own rules too. But basically, if you have an unprotected run of wire, OUTSIDE, of the structure, its pretty much OK to have it unprotected so long as the feed is "reasonable". Some say 5', some less, some more.....

I see another post where "advice about code" gets deleted. Hope that does not occur here. I am certainly not eliciting advice that would be in contradistinction to code. However, knowing code these days is a bit of a rabbit hole.........

My advise would be to go to your local inspector and explain to them what you want to do and see what they say. They are the one that will eventually have to sign off on it.

 

[Marcelo Zanetti]

My advise would be to go to your local inspector and explain to them what you want to do and see what they say. They are the one that will eventually have to sign off on it.
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Best advise.

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