Subpanel feeder ampacity

[Guest]

I am going to hang a 200-amp meter/main combo on the outside corner of my garage at the front of the house. On the back wall of my garage there is a 12/24 125-amp subpanel with lugs. Additionally, I cut in another 12/24 125-amp subpanel in my 3rd bedroom behind the door.

QUESTION: What size feeder should I use to the subs? I either want to go 90-amp, 100-amp, or all the way to 125-amp depending on what is the most cost effective. Should I go aluminum or copper? If so, what size wire do I need. I'll go with x/3 w/ground Romex. Panel #1 is about a 35' run and panel #2 is about a 70' run. THANKS!

 

[rich000]

Re: Subpanel feeder ampacity

The size feeder to these subs will be based on the load of these panels. The cost difference in the 3 breakers you are describing is minimal.

I prefer to run copper whenever possible. Again the cost difference for these size runs are minimal.