Where are these requirements found in NEC?

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jeff48356

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Livonia, Michigan
Can anyone tell me the references in the NEC book to these commonly-known codes? I realize that they are both required, of course, but can't find the specific reference in the NEC:

1) Unfused service conductors are not allowed to be installed inside of a house. A disconnect box outdoors is required, and service cable with an insulated neutral is required.

2) Wiring on basement concrete walls needs to be in conduit; NM cable is not allowed to be used.
 
Your first one is 230.70.
Don't know of a requirement for your second. See Art 334.
 
In my opinion the NEC does not really require either of those items. It is entirely up to the AHJ to decide.

For instance in my area it is common to run service conductors inside a building for about 5' to reach a panel.
 
iwire said:
In my opinion the NEC does not really require either of those items. It is entirely up to the AHJ to decide.

For instance in my area it is common to run service conductors inside a building for about 5' to reach a panel.
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10' is allowed here.
 
IMO both statements are false. If the panel is inside of the house then the "unfused" conductors are also inside of the house. The NEC makes an undefined allowance for entry into the structure.
 
I guess I'm mainly referring to houses which have had family room additions put on the back, and the area includes the location of the original service when the house was built. Now the service has to be relocated to the outside of the family room addition, which puts it about 15' away from the original point. You wouldn't be allowed to simply use SE cable from the new meter socket and run it under the crawlspace of the addition down to the basement; you would need a disconnect outside next to the meter, and use SER cable (SE cable with an insulated neutral and separate bare ground) fed off a 100A breaker (or whatever size is now required to handle the new load).

I didn't see any reference in NEC prohibiting such an installation or requiring the disconnect box.
 
again... the reference for what you are asking is 230.70, specifically 230.70(A)(1), but, as rob points out, the distance allowed is not specifically given by the NEC. The allowance may vary by jurisdiction, inspector or job.
 
augie47 said:
again... the reference for what you are asking is 230.70, specifically 230.70(A)(1), but, as rob points out, the distance allowed is not specifically given by the NEC. The allowance may vary by jurisdiction, inspector or job.
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I agree with Gus, that is the code referance.

You might also want to look at 230.6 for some ways to keep conductors that are inside the building outside to the NEC.
 
The rule I've seen enforced is that the service entrance cannot extend more than 8 feet inside of a building without a disconnect, but there is no restriction on the length if run on the exterior of the structure. I'm having a hard time locating the specific reference, so it may be a state code; however, I think it might also be a reference to the 10 foot tap rule, 240.7(B).
 
macrae said:
The rule I've seen enforced is that the service entrance cannot extend more than 8 feet inside of a building without a disconnect, but there is no restriction on the length if run on the exterior of the structure. I'm having a hard time locating the specific reference, so it may be a state code; however, I think it might also be a reference to the 10 foot tap rule, 240.7(B).
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230.70(A)(1) says "either outside of a building or structure or inside nearest the point of entrance". It does not give any specific distances. Local AHJ's often set their own rules here as to what distances they will allow. Some do decide you will not enter a building at all without some overcurrent protection, but most will allow you to enter at least through a wall if you put the overcurrent device immediately inside or within maybe 3 to 5 feet upon entering.

Tap rules in 240.21 only apply to feeders, which will have an overcurrent device ahead of the conductor being tapped, just happens to be at a higher protection level then otherwise allowed.
 
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