Hello to all. I have been lurking on this board for some time, and now I finally have a question. Do the conductor ampacity tables of the NEC apply to DC systems? I would think so since it only states voltage ratings, and does not specify AC only. Am I way off in my thinking? I have worked with DC motors and control, but never had to size anything.

Yes it does.

-Hal

I would agree that it does, since the NEC refers to signal and control circuits, as well as fire alarm circuits. These all (can be designed to) operate on DC.

Thanks, I was starting to wonder.