Can anybody explain why in a 3 phase 4 wire system the unbalanced currents return path is in the neutral, while when you have a phase-ground fault it is through the ground? I'm envisioning two wye systems which are connected by an equipment ground wire, and the neutral on each side is bonded to the ground bus. I don't understand how the return current (assuming the phases are not perfectly balanced) knows the difference between the ground wire and the neutral wire.
Any help is appreciated. Thanks!
Any help is appreciated. Thanks!