When trying to find pipe size for USE cable, the charts don't show USE that I can see. I know that USE is underground cable, but my supply houses don't supply aluminum wire except in USE. Is there somewhere in the code that specifies what USE is equivalent to, in insulation? I am thinking about the options of using # 1 USE aluminum for a feeder to a 100 amp panel, instead of #3 copper. I'm figuring up a bid on a job. The run will be approximately 100ft. Thanks

Measure the USE at the widest dimension, then use that as the diameter of a circle for the single conductor that will fit in the pipe. (53% of internal sq/in)

If the wire your supply house has is only marked type USE it can not be used for inside wiring. See 338-10(4)

I don't have much experience with USE cable since it is not stocked at most supply houses in my area but I believe it is frequently also listed as type RHH/RHW.

Remember it will cost more for the larger conduit to use AL wire so it probably will not save much if anything.

Curt

Thanks for the replies, I have decided to bid with copper wire. That was my first choice. I was just juggling figures to see the difference in price. Curt, you are right about the pipe size. I would have to increase the pipe size, and with all the other factors involved, copper is the way to go. Better job also. Thanks again for your input. Steve..

It might also be pointed out that type USE is not permitted as a interior wiring method.

Thanks for the info again.. "USE shall not be used in interior locations That settles that question for me. Didn't think to look in the code for that one
So many do's and don'ts in this trade. A lot to keep up with. Thanks again.. Steve