Cable size for under ground electric service connection.

[tevake]

I need a bit of info help.

I'm wanting to get 200amp service routed underground about 125 feet to the shop building on my place, then on over to a polebarn about 80 feet further.

What size wire should be used and is it best to put it inside conduit?

Pics of the shop rebuild to follow.

Thanks, Richard

[Zeke]

A lot of folks are using mobile home feeder which is an AL direct burial cable. It comes in sizes up to 4/0 and that is good for 200 amps. Sorry, don't know the distances off hand. Just wanted to mention MHF because it's economical.

Conduit is good for many applications but not always necessary.

There are tons of wire size charts on the Net.

Here is a good calculator. Use 120v as your value since you are running 2 120v legs, a neutral and a ground.

Also, I looked up MHF for that distance and 4/0 is not enough.

[RWebb]

I'd send an Email to the utility and ask. Email over phone call as you then have a record...

also check local codes some deviate from NEC...

[URY914]

Originally Posted by tevake

I need a bit of info help.

I'm wanting to get 200amp service routed underground about 125 feet to the shop building on my place, then on over to a polebarn about 80 feet further.

What size wire should be used and is it best to put it inside conduit?

Pics of the shop rebuild to follow.

Thanks, Richard

From what you've said the size is about 205'.

[MBAtarga]

Depending on the type of wire used, conduit would be against code.
What is driving the need for 200A service?
If you only need a few lights and outlets in the polebarn, you could decrease the cable size from the shop to the barn.

[tevake]

Zeke, thanks for the mention of the MHF. And that link to the calculator, helpful.

RWebb, you would think that the power co would be happy to share that info, but they refer you on to a lic. Contractor to get the design specs. Done.

Thanks Paul, not sure why that had escaped me. 👋

MBA Targa, we have two RVs along the run with ACs or heaters, plus appliances and tools in the shop. As well as running a well motor, it does add up.

Thanks guys for the useful input.

Cheers Richard

[wdfifteen]

Originally Posted by tevake

RWebb, you would think that the power co would be happy to share that info, but they refer you on to a lic. Contractor to get the design specs.

They just want to sell service to your meter and don’t want liability for anything beyond that.