Installing Electric To The Barn

[Hoeman00]

I ran 200 amp to the house and 200 amp to barn.
In the shop my Lincoln welder will trip a 60 amp
breaker after welding for a while (I replace breaker
after it starts tripping frequently).
Air comp takes 25+ amps and sometimes run both
at same time.
Also didn't like running thru house box (200 amp and
100 amp circuit to shop) and lights dim when working.

 

[Makers_Mark]

<font color=blue>What type of wire is needed for an underground 200 amp feed in plastic conduit (say 400')? </font color=blue>

I have the same question. I'll need to run 100-200 amp service into my workshop for welders, plasma cutter, compressor, etc. I already have seperate service for my barns. I'm thinking of upgrading that to 200, then breaking off to another 100 amp box. Does this sound do-able? It sounds smarter to run the wire through conduit rather than drop it straight in the ground.

 

[Anonymous Poster]

I would run 4/0 copper with a 2/0 ground. Min. 1in. conduit. (4 #4s max)

 

[Anonymous Poster]

Any wire buried directly in the ground has to be rated for such use. Also 200A in aluminum would have to be sized either 250 or 300mcm depending on the type. Aluminum isn't as good a conductor as copper, thus the upsizing.

 

[Anonymous Poster]

Off a 200 amp service, you can run up to two 100A sub panels. Direct burial or conduit is ok. I used conduit just so I could run future wiring thru it as needed. Sub panels must have a disconnecting means.

 

[beenthere]

WOW!! That question sure got a lot of response, and very good information. But the project just got a whole lot more expensive. /w3tcompact/icons/frown.gif

I would only add that when I did the same thing (electric to shed), I also added a 12-3 cable so I could switch power on or off from the house. That way I could plug in the block heater and turn it on from the house, usually an hour or two before I wanted to head out to start the tractor. I also have a yard light at the shed that I can turn on/off from either the house or the shed.

Trev. I think the contractor who buried your wire 6' under was also thinking more of his pocket than any need to bury wire that deep. IMHO, it isn't necessary at all. Water pipes maybe, but not electric. Unless he thought you were going to get rambunctious with your 4300, and start digging some real deep holes. I am not sure if the diggers hotline could even locate your wires that deep in the ground. But for most reasons, they wouldn't have to.

 

[boustany]

My 2 cents (I done it it) is bury the fattest 3 conductor cable you can afford (Of course 3 conductor means red, white, black, and ground). You may figure you'll save money with 12/3 or 10/3, but the amound of effort and expense running the wire will be more than that. If you put in a 12/3 you'll be saying "why didn't I bury a 4/3" for the next 20 years.

Basically, set up a sub-panel, even a really small one. So you'll have a 60 amp subpanel in the barn with 4 or 8 circuits. This panel will be fed off a 60 amp breaker in your main box. I think most codes require you to keep ground (copper) and neutral (white) separate in sub panels.

In any event, find out what local codes are, and check before you dig. Its a good idea to run the cable through a pipe or simething, but cheap corrugated drain pipe will do ok. I ran the 'phone while beside the pipe and had no problems.

Of course, if you don't already have a backhoe, this can be a great excuse to use on your spouse to buy one...

 

[RobS]

If you do go with aluminum I'd have an electician handle it for sure. There are some special coatings etc. to handle the dissimilar metal corrosion with the copper. The house I grew up in was built with aluminum wire throughout and almost burned down several times /w3tcompact/icons/shocked.gif

 

[kcbarnes]

You have good info so far, but one thing I have done is run a 1 1/4 to 1 1/2 pvc all the way and only run #10 for a couple of circuts for my needs now and then I could always pull out the small wires and install a 60 or 100 amp service later with no digging. Run a 3/4 pvc for the phone.

 

[jmattox1]

I am glad you caught that on the 10awg, RayS. If someone else wouldn't have said somethin I would have.