I have a new 1500 sqft pole barn that needs electric. I expect to need 100Amp service at the barn which will have a 220V 15A compressor and 220V 25A welder. The rest of the barn will be 110V fluorescent lights, and few if any high amperage tools. My house has 200A service, and I could branch off a 100A breaker from the house breaker box.
My first question is: Can I run 275 ft of underground feeder wire (in pvc, 24 inch burial) to this barn from a 100A breaker at the house? I’ve done some calculations that suggest #1 aluminum feeders would be good, and the voltage drop should be less than ~3%. But most calculators stop at 250ft, and runs over 250 ft aren’t discussed much. I want to ask here because the experience is unmatched. The house has a good 3-wire feed and breaker box. But the house is all electric. I’m willing to go with copper feeders if I have to.
I plan to use two 8ft deep copper grounds at the barn.
I done a lot of research and can’t find a definite answer on maximum feeder lengths. BTW our state uses the 2014 NEC codes, but I’m all about safety.