Sorry this is so long but I need to describe the whole thing.
After an electrical storm, one of the kitchen GFIs was tripped. Everything was unplugged from all receptacles on the circuit. When the GFI was reset the breaker tripped. Resetting the breaker caused the GFI to trip again. This cycle was repeated several times.
Then it changed so that turning on the breaker caused the breaker to trip immediately.
With the breaker off, a working ohm meter showed no connection between the hot and the neutral or ground. So it appeared as if either AC or a higher voltage was required to see a short & trip the breaker. (Remember this whole thing started during a thunderstorm).
I started disconnecting the receptacles & junction boxes one at a time trying to isolate where the problem was. I saw no damaged wires. I did not know the order in which things were connected so I'm sure the order I did the disconnects was not the best.
Eventually I could turn the breaker on without it tripping so I started connecting things back one item at a time, testing after each reconnection until everything was connected as it originally was. The problem was gone. I tried wiggling the wires I could reach but the problem stayed fixed. That was several weeks ago.
Now, immediately after another electrical storm the problem is back.
What is going on? In giving an answer, please keep in mind:
- The problem has appeared twice following a severe thunderstorm
- An ohm meter showed an open circuit but it acts shorted under 120 VAC
- No apparent physical damage to the wires.
- The breaker stays on with the GFI connected but nothing downstream connected.
- The problem went away (until the next sever thunderstorm) after dis/re-connecting everything.
MANY MANY thanks for any help.