...using ground to test with? 100 volt ac unit. tested common wire to ground had 38 volts ac, test hot wire to ground 110 volt ac, why is there 38 volts ac on neutral
Need a little more information. Is the ac on a dedicated line? What was your reasoning for testing the line? Did you test from hot to neutral... what was your reading? If you are getting 110v hot to ground then you should get 110v hot to neutral. If you are not getting that reading the neutral is open in the circuit somewhere. The neutral is the return path for the hot. If it is open then you will get voltage on it (neutral to ground).
