Hi;

I have a detached two car garage and I want to wire it. There is a small concrete patio that we poured between the house and garage. We put a 1 1/4 inch PVC under the ground and brought it into the garage. My father in law ran 12/3 THWU through the coduit and left it unattached. I want to provide enough power to the garage for possible future expansion. I really don't need a ton of power but you never know. My house panel is 200amp. I asked some people what they would run for a one man weekend hobby shop. Most agreed that 40-60 amps would be sufficient for your basic tools/comprssor/lights. I had to pull the 12/3 out because I wasn't convinced this is enough power for future possible expansion. I am thinking of running 6/3 for 60 amps or 8/3 for 40 amps. What would you suggest (keeping in mind that the conduit comes up out of the concrete floor and I had to open up a small hole which will be filled in to get the wire through the 90 of the conduit I don't want to do this again).

Thanks

I would suggest you go with 6 AWG and a 60 amp panel since you want future expansion and are unsure of how much you might need. Be sure the panel you get has a main breaker so it can serve as the disconnect for the structure.

You need 4 conductors in that conduit, not 3. Two hots fed from a breaker in the main panel, one neutral and one grounding. I'd use THWN wire. At the sub panel you need to keep the neutral and grounding separate which means you will probably need to buy a ground bar and remove the bonding screw or strap in the sub. Since the garage is detached you will also need to install a ground rod and 8 AWG copper conductor from it to the ground bar in the sub panel.