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Posted By: George Little NM Cable entering boxes. - 11/16/14 06:45 PM
The question came to me about how far must the NM cable sheath enter the boxes? I could only find the information located in 334.15(C). Nothing about entering the box sans the conduit. My answer would be, the sheath must extend beyond the clamping device be it a non-metallic box or a metal one. The person calling me was concerned because his boss wants the sheath to be at least 3/4" into the box.
There's got to be more important things than this dispute.
Posted By: HotLine1 Re: NM Cable entering boxes. - 11/17/14 12:32 AM
George:
From 314.17 (C) of 2014 NEC.....

Where nonmetallic sheathed cable or multi-conductor Type UF cable is used, the sheath shall extend not less than 6 mm (1/4 in.) inside the box and beyond any cable clamp. In all instances, all permitted wiring methods shall be secured to the boxes.

Posted By: gfretwell Re: NM Cable entering boxes. - 11/17/14 07:44 AM
1/4" in english
Posted By: ghost307 Re: NM Cable entering boxes. - 11/17/14 09:10 PM
Yep, 1/4" minimum.
Posted By: George Little Re: NM Cable entering boxes. - 11/17/14 11:45 PM
Thanks Guys. You are the best. I would have expected it to be in Article 334 but it wasn't. HEY Inspectors have every right to be wrong :)) And I'm probably one of the few that would admit it.

That's what this BB is all about.
Posted By: HotLine1 Re: NM Cable entering boxes. - 11/18/14 02:50 AM
George:
As I say to some..."I'm human, I do make mistakes too"
Posted By: gfretwell Re: NM Cable entering boxes. - 11/18/14 04:20 AM
I guess it is because there is more than one kind of cable and they were trying to avoid the mess that was created when they put a cable rule in 320 and referred to it in all the other cable articles. (like accessible attics in 330.23 334.23 etc)
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