0 members (),
205
guests, and
28
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
|
Joined: Jul 2004
Posts: 9,928 Likes: 34
OP
Member
|
Is there a violation if you used a cable with another conductor or two in a raceway system? (example a 12-3 w/g Romex and an additional THHN for the 4th ungrounded conductor in a 3/4" raceway). It didn't sound right when I heard it but I am not sure what you would cite.
Greg Fretwell
|
|
|
|
Joined: Apr 2002
Posts: 7,381 Likes: 7
Member
|
That's interesting... I must say none of the rocket scientists here thought that up....yet! Time to ponder what (if anything) to cite.
FYI: another reason to add common sense to the NEC?
John
|
|
|
|
Joined: Aug 2006
Posts: 356
Member
|
can you install NM cable in a complete raceway system? Or only in a piece of raceway just for physical protection?
Be kind to your neighbor, he knows where you live
|
|
|
|
Joined: Jul 2004
Posts: 9,928 Likes: 34
OP
Member
|
I can't cite any rule that says you can't have NM cable in a raceway system. Since all circuit conductors come through the same connector there are no inductive heating problems. I know this is ugly but I am stumped to come up with a violation.
Greg Fretwell
|
|
|
|
Joined: Jun 2004
Posts: 1,273
Member
|
It's not a violation.
However, due to economics you'd not expect to see it.
It's generally impractical.
Tesla
|
|
|
|
Joined: Nov 2007
Posts: 764
Member
|
I’m wondering if 300.3[B] and 300.3[B],1 might apply if the conductors are all part of the same circuit, since both also state the same "cable or cord" as well. Something else maybe, is that 334.15[B] is for exposed work, so not sure if this would preclude the NM from being run in a conduit that is concealed or partially concealed.
|
|
|
|
Joined: Jul 2004
Posts: 9,928 Likes: 34
OP
Member
|
I suspect the RX was there first and the THHN was added.
KJay, this was all exposed in a garage/shop. A 240 2 pole was converted to 120/240 3 pole from what I could assume. I see RX in pipe quite a bit, just because that is what resi guys have on the truck or what homeowners buy at the HD. I bet 99% of it is fed into the pipe as they build the system just because of how hard it is to pull RX in pipe. I think part of it is you can buy RX cheaper than THHN if you don't want 500 feet.
I was not AHJ, just asked if it was legal as "gee whiz" info.
Greg Fretwell
|
|
|
|
Joined: Nov 2007
Posts: 764
Member
|
I guess technically you might be able to say that EMT fittings are not designed or listed for use with NM cables, since I see where 300.15 says that fittings and connectors shall be used only with the specific wiring method for which they are designed and listed.
IMO, I don’t think the NEC allowing NM to be sleeved for protection was intended to allow unlimited use like that, but I’m also not sure exactly where to find a specific rule prohibiting it.
|
|
|
|
Joined: Apr 2002
Posts: 7,381 Likes: 7
Member
|
Kjay: The fittings you reference above are EMT, and used on the EMT, not the NM as I understand Gregs description. 300.15 would be a bad cite.
I tend to say there is nothing to directly cite, unless at the begining of the circuit, there is no 'from-to' connector.
John
|
|
|
|
Joined: Nov 2007
Posts: 764
Member
|
Kjay: The fittings you reference above are EMT, and used on the EMT, not the NM as I understand Gregs description. 300.15 would be a bad cite.
I tend to say there is nothing to directly cite, unless at the begining of the circuit, there is no 'from-to' connector.
True. It was just something to mull over. My thought was that NM is a separate wiring method with its own installation requirements and listed connectors, etc.
|
|
|
Posts: 44
Joined: July 2013
|
|
|
|