How do pilot isolation transformers provide insulation for high voltages when there is a difference in ground potential between substations? What happens when there is a difference in ground potential between substations due to a ground fault?
Ah right thanks, that makes more sense. What would happen if phase A had an SLG fault on the grounded Wye secondary? Would it appear to be a phase to phase fault between phase A and phase B? And for an SLG fault on phase B it would appear to be a phase to phase fault between phase B and phase C...
When a ground fault occurs on the secondary side of a Delta/Wye Transformer which has it’s Wye secondary grounded, how does the Primary see it as a phase to phase fault?
