ECN Forum
Posted By: rc NEC 300-14 - 02/15/01 05:28 PM
NEC 300-14 requires at least 6"of free conductor to be left at outlet boxes. The question is--- Two NM-Bs come into a single gang box. Does it meet the intent of the code to take the two grounding conductors and slide on a crimp sleeve and crimp at the face of the box and then cut off one of the grounding conductors at the crimp sleeve leaving the cut off ground stopping at the face of the box?
Posted By: Tom Re: NEC 300-14 - 02/15/01 05:42 PM
When you're all done making your splices, you should still have 6" of conductor left. The method you discussed would leave one equipment ground too short. If you want to use that method, one of the cables needs to be about a foot long. The other option, which I personally prefer, is to pigtail the equipment grounds. This is where you can use up some of your short pieces of scrap wire.
Tom
Posted By: sparky Re: NEC 300-14 - 02/15/01 09:33 PM
rc;
300-14 is really just addressing past sins in the trade.

The intent is free conductor, or conductor available for that sparky who is changing out worn devices 20 yrs from now.

I install exactly as you descibe, with one twist, i take advantage of 336-18's 12" and loop my incomming NM over the box neatly, to allow it to be pulled in by said future sparky.
[Linked Image]
Posted By: Glenn Re: NEC 300-14 - 02/15/01 11:55 PM
Sparky,

What do you do about the 8" requirement for the single gang PVC box of 370-17(c)Ex.?

Glenn
Posted By: sparky Re: NEC 300-14 - 02/16/01 12:34 AM
Glenn;
I believe that EX is in reference to those cheap boxes that do not hold the NM sheath.

I like to use the "accordian" method by which all conductors are folded into, and can fold out with, a device.

This is better done with a those plastic boxes that secure the cable.

If you really take a close look at those cheaper boxes , you could stick your pinky in it, even with a cable in the KO , evident by the last sentence of the EX.

The end result of this style box is an accumulation of dust, dirt and even larger debris over time.

This alone should constitue an "unused opening to be sealed", but that's another thread

[Linked Image]



[This message has been edited by sparky (edited 02-15-2001).]
© ECN Electrical Forums