I know this basic question has been answered before by reference to 334.30(B), but there's an aspect I don't understand. Does 334.30(B) allow unsupported installation if 334.30(b)(1) OR 334.30(b)(2) are satisfied or only if BOTH are satisfied.
My situation is finished walls with some ungrounded NM leading to three-prong sockets (I already added GFCI protection, but I'd like a physical ground too) and a couple of places with 14-gauge NM on 20-amp circuits. I have already replaced some by adding grounded NM drilled and fished from the attic crawlspace through the top plate, down through the horizontal fireblocks and down to receptacles near the floor. It's stapled near where it goes through the wall's top plate and it's clamped in the new box (old work boxes, but the kind that screws into a stud, not the kind with the useless blue tabs).
I'm satisfied that it qualifies under 334.30(B)(1) as being fished through an enclosed space and that stapling is impractical, but I'm wondering if I'm also required to comply with 334(B)(2)'s requirement of no more than 4-1/2 feet between attachments. It seems that it wouldn't make sense to require attachments every 4-1/2 feet where impractical, but it also seems like the code is missing the word "or" between parts (1) and (2).
I'm worrying about nothing and my installation complies with 334.30(B), right?
Best Answer
You should be fine. 334.30(B)(1) allows you to leave the cable unsupported where it's fished through a finished part of the building. Which is what you're doing.
334.30(B)(2) removes the requirement to support the cable within 12" of an enclosure, as long as you're within 4 1/2' of the last point of support, you're connecting to a luminaire or other electrical equipment, and the cable and point of connection are within an accessible ceiling in a residential dwelling.