Running Power To An Outbuilding

I want to have electricity in an outbuilding (that I haven’t built yet) so I can run an arc welder and charge my Elec-Trac electric garden tractor.  Plus power makes everything work better.  I’ll start with just a 12′ x 8′ shed to mount an electrical panel in and in the future when I get some money saved up I’ll build a full-sized pole barn and I hope to have to re-work as little of the electrical as possible.

20160621_183854.jpgWhen I got electrical service run to my house during construction I elected to spend a little more and get a 400 Amp service.  This meter panel is designed to feed two different breaker panels of 200 amps each.  So I have one 200 amp line going into the house and now I can add one more 200 amp 240V  line for my outbuilding.  Notice the open lugs available.  To carry the amps I need what is called 4/0 direct bury wire.  This means I can just did a trench 2′ deep and lay the wire in it and cover it back up.  In my area the 2′ depth is required and also I’m supposed to bury some yellow caution tape 6″-12″ in the trench to serve as a warning in case someone starts digging in the area.

This wire is about $2/foot so you want to measure as close as you can and not buy too much extra.  I also ran 2″ plastic conduit under where I will be adding more concrete to my driveway, just in case.  However these three wires take up all of the 2″ conduit, so I cannot add anything else.  But if I ever have to make a change I’ve got conduit running under my driveway.

Keep in mind the amount of power in the meter box can kill you.  While there is no danger in what I’ve done so far, since the wire isn’t hooked up to anything, unless you are confident in what you are doing you would be better off hiring someone to do you electrical work.  After having said that, I do all my own electrical work based on the small amount of training I had in the program I went to in Community College 30 years ago.