On Fri, 12 Apr 2013 18:33:08 -0500, "Pete C."
wrote:


Art Todesco wrote:

I know that you are not allowed to mix, say a low voltage line in a
conduit with line voltage wires. My question is, can you mix them if
either the line voltage wires or the low voltage wires are in their own
"conduit" inside of the larger conduit? I have a 2" diameter plastic,
flexi conduit going from my house to an area out by the road. Right now
it is used to bring 120 volts to a post lamp and an outlet in its base.
Now, if I wanted to run some low voltage lines, could I put them in a
piece of Greenfield (grounded of course) and run that Greenfield with
its low voltage wires, through the same conduit?

I'd certainly think so. Innerduct is common enough inside a larger
conduit, and I don't know of anything in the NEC that cares about
anything beyond the conduit enclosing a particular wiring. If wiring x
is good inside conduit x it shouldn't matter if the whole thing is in
larger conduit y as long as the conduit y fill specs are ok.

My normal recommendation is that when someone is running conduit they
run extra for potential future uses since conduit is cheap, particularly
PVC conduit. In a case like yours I would have suggested parallel runs
of 3/4" PVC conduit for just such future cameras, intercoms, gate
operator controls or whatever.
I "think" it boils down to if it is considered a "conduit" or a
"raceway" Can't use NMD (or metallic sheathed either) cable in a
conduit, but I believe it is acceptable in a raceway. Cables of
different voltages are allowed in a raceway. Wires of different
voltages must be segregated in a raceway.
Wires of different voltages are not allowed in a conduit. Can a
"conduit" be used as a "raceway"???