Sizing a pull box

[shockman]

When sizing a pull box for a riser. Five three inch conduit in arow .please tell me what size the pull box be for a striaght pull.Under 600 volts

[ June 18, 2003, 09:02 PM: Message edited by: shockman ]

 

[james.burns]

Re: Sizing a pull box

314.28(A)(1)
Under 600v 24" minimum

 

[bob]

Re: Sizing a pull box

314.28(A)(1)specifies 8 times the largest conduit diameter. 8 x 3" = 24". This is the minimum. Do your self a favor an make it longer and wider.

 

[frenchelectrican]

Re: Sizing a pull box

314.28(A)(1) 24 inch is min but i generally multiply by 10 it have alot more room to deal with it and you say 5 in a row remeber the spaceing between conducts i genrally keep a 2 inch apart with wide box and if pulling straght 30 inch by 30 will do it other wise if change driction then go wider and multiply by 14 the reason is the wire bending


merci marc

 

[iwire]

Re: Sizing a pull box

Bob and Marc sure are right about giving yourself more than the minimum if you can.

But if you are pressed for space and want to go bare minimum.

You could use 5 - 4" x 4" x 24" troughs pushed tight together.

For straight pulls the NEC is only concerned with the length.

The width (and depth) can be as small as the pipe will fit in.