I have seen panel changeouts where the new panel was much taller, but the installer just pulled the NM cable back into the new panel without removing any additional jacket. Sometimes this can mean more than 12" of jacket in the panel. Other than looking bad, I can't think of any reason to complain (not that I need much of a reason to complain, anyway!). I read a book about inspecting residential electrical systems, and there was reference to excessive combustible material (the paper inside the NM?) in the panel in these cases. Any other thoughts?
When I first got into the trade I was told that you couldn't leave an excessive amount of the outer jacket because the jacket covering the wire in the panel or in conduit could cause the wire to over heat. So to this day I leave about an inch of the jacket. Wirewiz
Re: How much (jacket) is too much?#13710 09/11/0201:55 AM09/11/0201:55 AM
I think the reasons that "neat & workmanlike" are rarely enforced is that there is no definition of it and "neat & workmanlike" doesn't belong in the NEC to begin with (no flames please, just explain how a job that is code compliant is unsafe because of neatness, see 90.1(A))
I usually go with about 1/4", for no other reason then that is what the first journeyman I worked for told me.
Few things are harder to put up with than the annoyance of a good example.
Re: How much (jacket) is too much?#13712 09/11/0207:04 PM09/11/0207:04 PM