Service Entrance Conductors

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ammklq143

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Location
Iowa
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Electrician
I have a project that has an overhead service coming down to the PoCo meter and then into a 100 amp disconnect. Out of the disc I have 2-2-2 and a #6 aluminum going to a 100 amp breaker panel. The conductors of the 2-2-2 have on the insulation "Type USE-2 or RHH or RHW-2". I got a call from the inspector saying that I couldn't use USE going into the building because NEC 338.12 (B) says Uses Not Permitted (1) For interior wiring and not (2) for aboveground installations except where USE emerges from the ground and is terminated in an enclosure at an outdoor location and the cable is protected in accordance with 300.5(D).

I understand that USE is not permitted in this application BUT this is Type USE-2 or RHH or RHW-2. Ok, so.....Under the definitions of 338.2 an SE cable has a flame-retardant moisture resistant covering. USE has a moisture resistant covering but not required to have a flame retardant covering. In the insulation tables in NEC 310.104 the table for USE and USE-2 say moisture resistant covering and heat resistant covering. It also says if more than one conductor in the cable refer to 338. The tables for RHH and RHW-2 say flame retardant and moisture resistant covering. Since the conductors have multiple insulation types and characteristics and from what I can see there's nothing prohibiting RHH or RHW-2 from being installed in a conduit entering a building to feed a panel.......wouldn't the cable that's installed work? I'm assuming the USE can't be used because it lacks the flame retardant feature but since the cable is also rated as other types of insulation that do have a flame retardant feature I think it should be able to be used.

So...what's the answer? One says you can't but the other two types say you can or at least don't say you can't.....?
 
ammklq143 said:
I have a project that has an overhead service coming down to the PoCo meter and then into a 100 amp disconnect. Out of the disc I have 2-2-2 and a #6 aluminum going to a 100 amp breaker panel. The conductors of the 2-2-2 have on the insulation "Type USE-2 or RHH or RHW-2". I got a call from the inspector saying that I couldn't use USE going into the building because NEC 338.12 (B) says Uses Not Permitted (1) For interior wiring and not (2) for aboveground installations except where USE emerges from the ground and is terminated in an enclosure at an outdoor location and the cable is protected in accordance with 300.5(D).

I understand that USE is not permitted in this application BUT this is Type USE-2 or RHH or RHW-2. Ok, so.....Under the definitions of 338.2 an SE cable has a flame-retardant moisture resistant covering. USE has a moisture resistant covering but not required to have a flame retardant covering. In the insulation tables in NEC 310.104 the table for USE and USE-2 say moisture resistant covering and heat resistant covering. It also says if more than one conductor in the cable refer to 338. The tables for RHH and RHW-2 say flame retardant and moisture resistant covering. Since the conductors have multiple insulation types and characteristics and from what I can see there's nothing prohibiting RHH or RHW-2 from being installed in a conduit entering a building to feed a panel.......wouldn't the cable that's installed work? I'm assuming the USE can't be used because it lacks the flame retardant feature but since the cable is also rated as other types of insulation that do have a flame retardant feature I think it should be able to be used.

So...what's the answer? One says you can't but the other two types say you can or at least don't say you can't.....?
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The answer is pretty simple, but the hard part will be getting the inspector to accept it:
When you have a wire or cable with multiple ratings, you can use it wherever any one of the ratings is allowed and you can disregard the others.

The inspector may be convinced by the statement that if his interpretation is correct a manufacturer would be foolish to multiply list it since that multiple listing would restrict its usability, not expand it.
Would he say that since it is also listed as RHH it cannot be used for direct burial?
 
This is similar to those recessed cans that are labeled "IC/Non-IC Convertible".

Simply: The cans are IC and allowed to make contact with insulation.

The way you "convert" them to Non-IC is to keep the insulation away from them.

In this case you could "convert" the RHW to USE by simply not running it in a place that requires flame retardation.

But yeah, good luck explaining that to the inspector.

Maybe point out that THHN is not for use in wet locations, but most THHN is also THWN. Then ask him if he's been failing a lot of inspections where electricians were running wire that was clearly marked THHN and put into a conduit on the outside of a building.
 
jaylectricity said:
This is similar to those recessed cans that are labeled "IC/Non-IC Convertible".

Simply: The cans are IC and allowed to make contact with insulation.

The way you "convert" them to Non-IC is to keep the insulation away from them.

In this case you could "convert" the RHW to USE by simply not running it in a place that requires flame retardation.

But yeah, good luck explaining that to the inspector.

Maybe point out that THHN is not for use in wet locations, but most THHN is also THWN. Then ask him if he's been failing a lot of inspections where electricians were running wire that was clearly marked THHN and put into a conduit on the outside of a building.
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Thing that is a little different with the dual rated recess cans for the ones I have seen is there is two labels. The non IC label is over the IC label and you peel it off if using as an IC application. When used as IC the lamp wattage limitation is lower then for the non IC.

OP is using same conductor no matter which marking applies to his condition. He could use it as 90C conductor instead of 75C if he sticks to the dry location requirements necessary to use the RHH rating. Now if it has a (-2) rating then it is a universal conductor with rating of 90C for wet, dry or underground direct burial.
 
If you present the inspector with cold hard facts, how can he deny you? If he does, go above his head. You CAN appeal, you know, but it may hold up your job (and your money). As such, sometimes it's cheaper to just do what the inspector says.
 
DrSparks said:
If you present the inspector with cold hard facts, how can he deny you? If he does, go above his head. You CAN appeal, you know, but it may hold up your job (and your money). As such, sometimes it's cheaper to just do what the inspector says.
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True that you have to pick your battles, I'd fight the OP's problem nearly every time though. Multiple ratings on a conductor means all those marked do apply to it, if it didn't what would be the purpose of multiple ratings?
 
kwired said:
True that you have to pick your battles, I'd fight the OP's problem nearly every time though. Multiple ratings on a conductor means all those marked do apply to it, if it didn't what would be the purpose of multiple ratings?
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Exactly, or else I'd have to carry TWN on my truck along with THHN for underground pulls!
 
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