12 years ago
OK, I have now established proper metal content. The issue is more of an
electrical code issue, and I'm hoping the wealth of knowledge of the
usual suspects can help me out.
My basement shop needs more outlets. I had a nice new breaker panel
installed a few years back, and it's time to add an outlet so I can run
my mill without first unplugging the lathe.
The basement is finished, and has a "half wall" of wooden tongue & groove
boards that ends about 10" below the bottom of the breaker panel box.
The top of the wall is capped with a piece of 2x molding. The wall is
built on 2x3 studs, and the plan is to mount the outlet box in the wall.
I can run Romex once I'm in the wall, but I need to get from the breaker
box to the top of the wall in a protected (and hopefully tidy) fashion.
My original notion was to bend up 1/2" conduit to bridge the gap. I can
drill a hole in the top of the wall large enough to insert an inch or two
of conduit. I can attach it to the breaker box with a standard clamp,
going in through one of the bottom knockouts. I would then snake the
Romex down through the conduit & into the wall.
The question is whether code requires any sort of bushing or clamp on
either end of the conduit. Loose wires run in conduit do not require
clamps. If the Romex was exposed where it came out of the conduit, a
clamp would be required that fits on the end of conduit. It would take a
much larger hole to fit the clamp down through the top of the wall, and
the Romex is never exposed anywhere.
For my own peace of mind, it would be nice to have a clamp of some sort
inside the breaker box to prevent anyone from accidentally yanking the
Romex out. One option would be to slip one of the one-way plastic spring
loaded NMSC clamps (the sort that usually go in a knockout) onto the
cable just where it comes up out of the conduit fitting.
Given that previous licensed electricians ran Romex exposed and
unprotected in other areas, I doubt anyone is ever going to get cranky
about whatever I do. However, I try to stick to code whenever possible,
and I'm at least curious as to exactly what the code might have to say
about something like this (if anything). It's a bit too peculiar for any
of my wiring books or the course I took years ago.