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I'm installing 200 amp service in a shop, and I am going to feed my house with a 100 amp sub panel. I want to use aluminum wire for this run. What gauge of wire I should use?

marked as duplicate by Tester101 electrical Jan 3 '17 at 19:07

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    You're planning to feed the house from the 200 ampere shop service? You want to know the wire size for the 100 ampere run, or the 200 ampere service? How long is the run between panels (along the wire)? – Tester101 Jan 3 '17 at 15:06
  • Depending on the run length, you may need to use a short section of wire as big as the breaker will take (I have almost the same setup, but I can't recall what the largest size the 100A breaker takes, just that it's smaller than what I actually wanted to go the distance with) and make a junction to larger wire for the distance in order to keep voltage drop down. – Ecnerwal Jan 3 '17 at 18:40