box fill calculation

[dm9289]

I was practicing box fill count calculations for a device box with 2 #12-2 wgnd entering a device box with a receptacle and a internal cable clamp and got a count of 8. 4 conductors - 1 gnd-1clamp-2 for receptacle. So i would need a 3x2x3-1/2 device box easy enough. However what I could not calculate was if I had 1-#12-2 wg and 1-#14-2wg and one internal clamp and one receptacle. I figured you would have to do a box volume calculation but I did not know how to represent the cubic inches for the receptacle or the clamps.

Please help I am studying for my test

 

[raider1]

For the receptacle you would use a double volume allowance for the largest conductor connected to the device.

For the clamp a single volume allowance should be made based on the largest conductor present in the box.

Take a look at 314.16(B)(2) and (B)(4).

Chris

 

[dm9289]

thanks alot Raider I looked up the article it is greatly appreciated

 

[raider1]

Your welcome.

Chris