Should all three lines be on the same line/phase?
02-24-12: Orelayer
Yes....
Should I keep the outlets a certain distance from each other?
Not really...
I would suggest not putting 2 duplex receptacles in a 2 gang box though. Reason? If you use any equipment that uses a wall wart in some cases the thing will cover part of the receptacle next to it.
How long will the branch circuits be? Distance from the electrical panel? Don't forget to figure distance up and down.
If the wire will be longer than 70ft or 80ft you might want use #10 awg.
I would also recommend solid core wire. Not stranded.
The electrician will hate working with #10 solid wire and probably try to talk you out of it.... If he uses deep old work cut in boxes he won't have any trouble with #10 solid wire.
Breaker size? 20 amp....
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