Electrical – 100 AMP garage sub-panel from 200 AMP house

electricalsubpanelwiring

I've checked a number of the other questions but not finding the specific answer I need.

I'm wiring a 100 AMP garage sub-panel from a 200 AMP main in my house. I plan to install a 100 AMP circuit breaker in the house panel. The run to the garage, lug to lug is ~65' and I have to bury the cable to meet code and am going to put it in Sched 40 conduit.

I'm thinking I can use 1/0-1/0-1/0-4 AL but since it needs to go underground am confused about SER vs MHF and hoping I can find a solution that doesn't require changing cable to go from underground outside to inside the house and garage. The NEC chart isn't particularly helpful to me.

Also, what is my option for copper instead?

Best Answer

Your options are a minimum of #1 aluminum or #3 copper.

Since it's only 65 feet I wouldn't upsize it for voltage drop.

You don't need service entrance or direct burial type cable if you are running conduit underground you can use type THWN wire. Individual wires not cable. If you don't want to run conduit you can buy direct burial type wire like You are talking about.

Good luck and stay safe!