Dedicated 20 amp circuit. 10/2 or 10/3?

I am pretty sure my electrician used #10 B and W, but #8 green to earth ground in PVC instead of Romex.

mnenasci    Dedicated circuits is a great idea. I have five 30 amp circuits for amps and two circuits for low power, 20 amp. The low power is a 30 amp sub panel fed through a larger Sola isolation transformer.

Upstairs has less than that.