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Plastic Box Fill with Integral Clamps

Do you count the integral cable clamps in a plastic box that has them towards box fill?

  • Yes

    Votes: 1 16.7%

  • No

    Votes: 5 83.3%
  • Total voters
    6
jar546

jar546

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We all know that plastic boxes are marked with their cubic inches along with some other info. Most 2 gang and octo boxes have integral clamps to hold the NM cable in place, simply by knocking it loose and the plastic tab puts pressure on the cable to hold it in place relatively secure. Single gang boxes usually just have knock-outs and don't have integral clamps.

Here is the question:

Does anyone out there count the integral clamps for box fill and deduct from the marked cubic inches?
Please answer the poll question, even if you post an answer below. Thank you.

box.jpg
 
NO - I thought the clamps in an non-metallic round or octagon box was already counted towards the cubic inches. The manufacture counts them as part of the box??
 
Pcinspector1 said:
NO - I thought the clamps in an non-metallic round or octagon box was already counted towards the cubic inches. The manufacture counts them as part of the box??
Click to expand...

Apparently not. The IAEI is very clear on their interpretation and I have read some articles in other electrical magazines that also counts the clamps. I don't agree with that.
 
I had to say no because I seldom, ya why lie......that’s never, count anything in a box. When I asked for a picture in your other fill thread I meant it. I look at the box and if it looks too full I ask for a fix. It’s always so obvious that nobody has complained.

If I practiced with it I suppose I could get that down to five minutes on a meps inspection. It might happen twice a day. Ten minutes isn’t too much to ask for. The next time a box looks too full I’ll ask for a stuff in the box count. They’re going to ask, “What size box do you want?” I’m going to say,”No no you guys.....just count the stuff“ and they’re going to say, “Dammit, the box is too full. You see it, we see it. Just tell us what size”.
 
Last edited:
jar546 said:
The IAEI is very clear on their interpretation
Click to expand...

Conductors, devices, grounds and clamps. Been that way since I started in 1979. All wiring methods shall be secured to the box, except for plastic single gang box. This is done in plastic multigang boxes with a factory supplied internal clamp - 314.16(B)(2). Call it integral or internal, its still the same.
 
Dang...I'd have to agree with jar, clamps need to be counted.

The NEC handbook has some good exhibits on counting conductors, grounds, devises (switch or receptacles) and clamps.

NEC handbook, "Don't leave home without it!"
 
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