The problem with sleeving NM cable through metal conduit is that it's not
bonded to the conduit and if it gets cut on the edge, the conduit could
become live. One issue with running NM in a conduit system which would make
it illegal is possibly the location of the conduit system. NM cable, like
THHN wire are not for wet locations. Therefore running those inside a
conduit system that is in a wet location, like underground would be illegal.
There is however no reason not to sleeve NM through PVC in a dry location
for added protection



"James "Cubby" Culbertson" wrote in message
...

" wrote in message
oups.com...

James Cubby Culbertson wrote:
"SQLit" wrote in message
...
NM cable is not rated to be inside a conduit system. I ran my pool
pump
with
12-2 NM for a month while I got the new conduit run. As long as the 6
is
enough for the load and distance.



I'm just curious, and not meaning to start a flame war here, but where
in
the code does it prohibit romex to be in conduit. I remember threads
in
the past where this was discussed and I can't remember what the outcome
was.
Cheers,
cc

Greetings,

a) Don't matter what the NEC says if your local inspector shoots it
down.

b) As I understand it you can run Romex in conduit. I have run 100's
of Romex wires inside conduit for additional physical protection. You
just can't run it inside a "conduit system" which means conduit
attached to a box at both ends or for extended lengths. You also must
provide a large enough conduit to prevent overheating. I try to use
3/4" for a single 12-2 or 12-3 NM cable to be on the safe side.

c) Today I ran 2 12-2 NM's inside a single 1/2" piece of EMT for 8 feet
with the yellow jacket stripped except for a few inches at the end for
a clamp. It's safe but you might have someone complain because the
wires inside NM don't have THHN written on them even though they are
rated at 90-105C.

Hope this helps,
William

Thanks William. Your letter (a) is right on! I tell ya, trying to
figure out all the code requirements is harder than the actual wiring of
just about anything! I just ran some circuits in my garage and I spent
more time thumbing through the code book looking for stuff than I did
doing the actual work. Probably why Electrician's charge so much!
Cheers,
cc