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.
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.
Iím 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.
#197000 - 11/04/1006:26 PMRe: Mixed cables and conductors in a raceway?
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.
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 donít think the NEC allowing NM to be sleeved for protection was intended to allow unlimited use like that, but Iím also not sure exactly where to find a specific rule prohibiting it.
#197004 - 11/04/1007:46 PMRe: Mixed cables and conductors in a raceway?