Small junction box calculation

[82angelfan]

I am planning on bringing (4) 3/4" conduits into the top of a pull box then bringing (2) 1" conduits out in my panel. Total of 13 circuits so 27 wires straight through. Do I actually need to do a j-box size calculation. A 6 x 6 x 4 should be able to hold 60

1" x 6 + 1" (4 x 3/4) would be a 12x12. i want to use a 6 x 6 x 4

 

[don_resqcapt19]

Assuming the conductors are 6AWG and smaller, you need to do a volume calculation as found in 314.16. No other calculation other than having a box large enough to fit the conduits is required.

 

[Dennis Alwon]

Assuming #12 wire the 6x6 should be fine but you may have to derate based on the number of conductors in the conduits.

 

[infinity]

What size conductors?

 

[82angelfan]

Assuming #12 wire the 6x6 should be fine but you may have to derate based on the number of conductors in the conduits.

Yes, I will derate in the 1". I will have to recalculate. The 3/4" will be broken up into less than 3 circuits per