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huntington beach, ca.
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Discussion Starter · #1 · (Edited)
Ok who posted that this is ok? Magnetta? I just got the call haven't looked in the code book yet. I used romex for the island underground in pvc. Don't tell me pvc encased in concrete is a damp or wet location.

Something I was always sure was against code, but I did it first time.
 

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You would have been OK most likely if you had not been underground. NM is not wet rated.....underground pvc is considered a wet location in concrete or not. Inspector may also have been a stickler about conduit fill if you ran 12 in 1/2". I'm thinking you may have been just over the one wire fill (53%)but I haven't made the calculation to be sure.
 

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I own stock in FotoMat!
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Underground is a wet location. NM can't go there. :sad:
 

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Article 100 Wet Location

Installations underground or in concrete slabs or masonry in direct contact with earth......:sad:
 

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Maker of Fine Sawdust
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Hell, as a woodworker, even I know you can't put NM in an underground condition. EIther use UF or THWN.
 

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I own stock in FotoMat!
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Next time try stranded THWN. It's much easier & it passes inspection.
Why stranded? Solid gets a green tag just as easy.
 

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huntington beach, ca.
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Discussion Starter · #9 ·
Hey i'm confused a little, it's not direct burial, it's in pvc conduit, in a slab, in the kitchen.

I know the correct way, I had just read a thread about it being ok to run NM in PVC, I just missed the part about the underground, plus I see it done in every house we remodel.

I'll just put in a female pvc connector and romex connector and strip the wire.
I used 1 1/4 conduit, 3 -12s and 1 -14 nm.
 

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The conductors in NM are required by Art. 334 to be constructed a certain way. That information is on the sheath of the cable. Remove the sheath, and you have removed the marking required by 310.11. Hence, removing the sheath of NM to install the individual conductors in any raceway is a violation.
 

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Stranded is for ease of pulling, not NEC. But you knew that.
I don't think two 90s in a run of ½" PVC which is probably not more than 20 feet long would pose too much of a problem pulling three 12s in. I doubt you'd have to break out the tugger. :smile:
 

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Head Grunt
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You would have been OK most likely if you had not been underground. NM is not wet rated.....underground pvc is considered a wet location in concrete or not. Inspector may also have been a stickler about conduit fill if you ran 12 in 1/2". I'm thinking you may have been just over the one wire fill (53%)but I haven't made the calculation to be sure.
X2, i always use UF wire and my inspector allows the 1/2" PVC but he is always very thorough on questioning me of exactly what i did. Stripping the NM in favor of THHN is a No-No and certainly wont pass. You should ask your inspector what he wants to see if you have any doubts. Every inspector is different in what they want to see. If you are going from one location to the next in PVC with no breaks then THHN stranded is the way to go for a much easier pull.
 

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I think you meant thwn for this application but I'm being picky...;)
I was always told (by those who know it all :rolleyes:) that nm conductors are thhn rated and do not carry the thwn-2 rating because the infused membrane (nylon) is not placed over the insulation. But there sure is a thin nylon covering or something from my experience....

But I've researched this quite a bit and to my knowledge NM-b conductors are the equivalent to thhn/thwn-2 conductors. I located a document that may lead to the answer or at least satisfy some of us. I found it in the Southwire technical library. So for what it is worth here it is and it is the best answer I can find as to why NM-b (modern nm) is rated for dry location and not wet and it has nothing to with the insulation or W rating or nylon coating. Why you can't strip off the outer sheath and paper wrapping and use the insulated conductors I have not found the answer.... other than there are no markings to show the rating on the insulation.... but... why would they do that if they cover the conducters with a sheath...saves time and money I suppose. But the ink doesnt change the wire for what it is....I suppose one just can't confirm what the wires/conductors are without markings. However, they also don't rate the cable or mark it on the outer sheath other than NM-b so UL and the manufacturer and the NEC are not wanting it rated as wet location applicable. So I guess you remove the outer sheath with a witness and and get a legal affidavit saying it was nm-b conductors....:thumbsup:
 

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I own stock in FotoMat!
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.........Why you can't strip off the outer sheath and paper wrapping and use the insulated conductors I have not found the answer.... other than there are no markings to show the rating on the insulation.... but... why would they do that if they cover the conducters with a sheath...saves time and money I suppose. But the ink doesnt change the wire for what it is....I suppose one just can't confirm what the wires/conductors are without markings. ........
You just answered your own question.
 

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You just answered your own question.
Yeah I guess I did but that wasn't my point. If you talk to Southwire technical the conductors in NM-b are solid thhn/thwn-2 without the markings. So IMO there is no safety failure/issue to put them in conduit with the sheath removed. You just can't prove that to an inspector. Personally I just never do it other than protective sleeves and I never strip it.
 

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Service & Repairs
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Ok who posted that this is ok? Magnetta? I just got the call haven't looked in the code book yet. I used romex for the island underground in pvc. Don't tell me pvc encased in concrete is a damp or wet location.

Something I was always sure was against code, but I did it first time.
Not me. Why would you accuse me of failing one of your jobs? :censored:

In your case here, PVC out to the island into a box (THHN/ THWN), and separate armored cables to each of your devices or appliances.
 

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Fentoozler
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If you talk to Southwire technical the conductors in NM-b are solid thhn/thwn-2 without the markings.

Being it cannot be proven what the conductors are - hence, a violation of 310.11 and subsequently 310.8 - NM-B cannot be used in locations other than "dry" [334.10, et al]

The rep would tell me they are XHHW conductors if it meant a sale for him.
 
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