I'm working on my first large mast service and I was wondering what you guys use for wire in the mast? I will be using 400 kcmil AL. I was thinking XHHW, but I was wondering if THWN was acceptable, or what was the standard wire type for the least cost. Thanks

Either THWN or XHHW can be used as long as they are marked Sunlight Resistant. I find that the Nylon starts peeling off THWN in a couple years and looks bad.

Curt