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# Will this be to code...pass inspection

#1
03-06-16, 06:08 PM
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Join Date: Sep 2006
Location: Minnesota
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Will this be to code...pass inspection

Hello. Please refer to the attached image. I needed a bottom mount box so I pieced PVC and metal together to get the volume I needed. Is there anything wrong with this? Is my use of the metal retainers on the sides OK? I will be getting this inspected and my state and town follow the 2014 national codes. Note I will be putting a second switch on the left side of the box. This is work in progress and I figured I'd check on the legality of this before finishing up

Thanks

#2
03-06-16, 07:08 PM
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Use a plastic ring or switch to a metal box.

Also the cable connector should be outside the box, not inside like on the left.

#3
03-06-16, 07:20 PM
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Looks like you are really hurting for space in that box. That connector on the left will be a problem even when it's installed correctly.

#4
03-06-16, 07:27 PM
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Join Date: Sep 2006
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Thanks. I'll get the plastic rings. As for hurting for space, the box plus the metal front is 32 cu in. And I have 2 switches and 10 wires, all 14 gauge. So unless my calculations are wrong, that takes up all 32 cu in. Did I miss something?

#5
03-06-16, 08:24 PM
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That would be a count of 15 times 2 cubic inches per.

#6
03-07-16, 04:59 AM
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Join Date: Sep 2006
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I'm not sure I understand your math. My understanding of the code is as follows:

10 wires at 14 gauge: 2*10=20 cu in
2 switches: 4*2=8 cu in
All ground wires: 2 cu in
All internal cable clamps (I.e. wire nuts): 2 cu in

Total: 32 cu in

You calculated 30. What did I miss?

#7
03-07-16, 06:05 AM
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Join Date: Feb 2006
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Box Volume

All internal cable clamps (I.e. wire nuts): 2 cu in
Correct the orientation of the clamp as directed above and this requirement will not be counted. Wire nuts do not count.

#8
03-07-16, 06:07 AM
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Wire nuts are not clamps, nor do they count towards box fill under the NEC. Clamps hold cables in the box.

#9
03-07-16, 08:00 AM
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Join Date: Sep 2006
Location: Minnesota
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Thanks...I assumed the clamps were the wire nuts and added 2 or 2.25 (depending on wire gauge) to every box to account for this. So I can subtract that number from all my future boxes.

I plan to remove those metal clamps and replace with the plastic ones. Or, could I just convert to a metal box? I assume there is no code issue with using a metal box in place of the PVC one in the picture. And I will reverse the clamps so the screws are on the outside.

Thanks!

#10
03-07-16, 11:47 AM
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The box and the extension ring can either both be plastic or both be metal, not mismatched. If you use a metal box, you'll need to bond your ground wires to the box via a green ground screw.

#11
03-07-16, 04:33 PM
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I only see two cables going into the box. Even if you used 14-2-2 that still only gives you 8 wires and one ground for box fill. Pigtails also do not count for box fill.

#12
03-07-16, 04:43 PM
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There are two cables from the right and one from the left.

You can see there are two white and two black wires in the box before the third cable is stripped.

#13
03-07-16, 04:59 PM
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That still is only 7 #14's. That switch looks like a 3 way but I don't see a red wire. Hummm.