Box fill

[paac]

I am studying for the Michigan Journeyman test, 2005 code.

I just want to be clear on something.

If you are calculating box fill and have 3 14-2 romex w/ground going into the box, you would count 6 for the current carrying conductors and 1 for the grounds for a total of 7, correct?

Thanks for all the help, this forum has been an invaluable resource to me.

 

[augie47]

as far as wire goes, yes. + allowances for devices and any internal clamps, etc.

 

[Dennis Alwon]

I am studying for the Michigan Journeyman test, 2005 code.

I just want to be clear on something.

If you are calculating box fill and have 3 14-2 romex w/ground going into the box, you would count 6 for the current carrying conductors and 1 for the grounds for a total of 7, correct?

Thanks for all the help, this forum has been an invaluable resource to me.

Yes but don't forget about devices and clamps, etc.

 

[chris kennedy]

Thats correct, as long as you don't have any of these in your box.

(2) Clamp Fill. Where one or more internal cable clamps, whether factory or field supplied, are present in the box, a single volume allowance in accordance with Table 314.16(B) shall be made based on the largest conductor present in the box. No allowance shall be required for a cable connector with its clamping mechanism outside the box.

(3) Support Fittings Fill. Where one or more luminaire studs or hickeys are present in the box, a single volume allowance in accordance with Table 314.16(B) shall be made for each type of fitting based on the largest conductor present in the box.

(4) Device or Equipment Fill. For each yoke or strap containing one or more devices or equipment, a double volume allowance in accordance with Table 314.16(B) shall be made for each yoke or strap based on the largest conductor connected to a device(s) or equipment supported by that yoke or strap. A device or utilization equipment wider than a single 50 mm (2 in.) device box as described in Table 314.16(A) shall have double volume allowances provided for each gang required for mounting.

Yeah, what Dennis said.

 

[paac]

as far as wire goes, yes. + allowances for devices and any internal clamps, etc.

Yes but don't forget about devices and clamps, etc.

Thanks. I was going to edit my post to say something about devices, clamps, etc. Thanks for keeping me honest!

Oh, thanks!

 

[Dennis Alwon]

Also be aware that a conductor does not have to be a current carrying conductor to count in the fill. You know of the grounds but also any wire that enters the box and is not used would also count.

 

[hardworkingstiff]

.... and 1 for the grounds ....

I've always wondered why you only count 1. They take up space just like the others.