winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
Bjenks said:I am not understanding your response... You would have the A phase and the ground conductors now carring the current in parallel.
Exactly. If a phase leg is intentionally bonded to ground, and also faults to ground at another location, there will be no significant change in phase current, and thus the breaker won't trip.
But this is exactly the same situation as a neutral to ground fault in a wye system with a grounded neutral. You have a _grounded_ conductor, which faults to bonded metal at an inappropriate location. There is no significant fault current flow, and thus breakers will not trip.
In either case, there is 'objectionable' current on bonded metal (EGC, building steel, etc.), and in either case ground fault detection may be able to discern this problem.
Because neutral conductors generally carry less current than phase conductors, I agree that the danger of a grounded conductor to ground fault is greater with a corner grounded delta...but have no way of quantifying 'greater'.
-Jon