1. Do i need a separate ground for the 110 and the 220 circuits or can I use 1 #12 as the equipment ground for the 220 and for the 110 circuits ground?
2. If my calculations are correct, that would be a total of 10 CCC and a ground plus the extra runs from the light switches back to the lights which is within the 15 limit for #10 or #12 wire in a 3/4 PVC. Since I believe that 10-20 CCC require 50% derate, would I need to use #10 wire rated at 40 amps and derate to 20 amps or can I still use #12 since they are not continuous load circuits?
Can anyone please offer some advice? I have no problem running cables and electric but want to be sure it is not a fire hazard. Thanks