Can 10 AWG handle 35 amps. For that service would use URD Aluminum 4 conductor cable need 2 hot neutral and should have separate ground to shop grounds isolated from neutrals in shop panel. 200 Amp Main Panel Wiring Diagram Electrical Panel Box Diagram Photos Good Pix Gallery Electrical Panel Wiring Electrical Panel Home Electrical Wiring Two-inch conduits are used to hold the copper and aluminum wires for 200-amp electrical service. What size wire do i need for 100 amp service . 2 2 THHNTHWN-2 Wire for 100 amp sub-panel. Needs to be buried in a conduit. Therefore if you need to run wiring for your 100-amp sub panel longer than 20 feet you should consider using a 1-gauge wire. - Click here for pricing on 3 gauge THHN wire. When installing a 100-amp sub-panel you will need to use either 4AWG American Wire Gauge copper cable or 2 AWG aluminum three-conductor cable. Single Conductor 2 gauge THHN Copper Wire. A 200 amp service that is being installed underground shoul...