Oilpan4 wrote: ↑Sun Nov 03, 2019 8:08 am
I don't think I have even seen a properly marked 2 insulated wire (black/white) with a bare ground wire romex or triplex cable used on a 240v circuit properly marked unless I put it there.
Ditto for me. I have to confess though...even when I've re-wired some of my own 240V circuits I didn't bother to mark the white wire as a hot. It's my house and it's obvious that the outlet and breaker are 240V so it is hard to forget that it's a 'hot' wire.
As for the US NEC rules for wire colors, my understanding is as follows:
For wire sizes <= 6 AWG
ground wires are green or bare copper. Green colored wires cannot be remarked for any other use, regardless of size.
neutral wires are white or gray, or a base color with 3 continuous white stripes
any other color (not green, white or gray) is a hot wire
For wire sizes 4 AWG and larger, wires that aren't green or white can be remarked since as Henry Ford said, you can get this size wire in any color you want as long as it is black.