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Pull Box Sizing over 1000V

Pull Box Sizing over 1000V

Pull Box Sizing over 1000V

I'm trying to design a pull box and I am having difficulty interpreting NEC 314.71 for the sizing requirements. I have a straight pull through the junction box and it states that the length of the box needs to be 48 times the outside diameter, over sheath, of the largest shielded conductor or cable. I am running (3)750kcmil & (1) #2awg 15kV shielded cables into and out of the junction box. The O.D. of the 750kmcil cable is 1.75", the O.D. of the #2awg cable is 1.0”.
So do I need to make the box 48x1.75=84” long or 48x1.75+(2x1.75)+1=88.5” long? Any insight into this would be greatly appreciated.

RE: Pull Box Sizing over 1000V

That is how I read that code section and I don't see any exceptions that would permit a smaller pull box.

RE: Pull Box Sizing over 1000V


RE: Pull Box Sizing over 1000V

Sorry, I did not read the last part of the question correctly. The size is based only on the cable or conductor with the largest OD and mcgyvr is correct.

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