Without getting into why some things are done the way they are done in Bosnia here, I will ask my question.
I recently had a service call for a power failure. I went to the location and inside the building was a sub panel fed off a main panel just outside. The fault was unknown but was causing the main breaker to trip outside. Over here they use a G.F.I. breaker in alot of cases and this was the breaker that was tripping. It is very common over here to find local tradesmen tying neutral to ground in a device or receptacle. This causs alot of problems for me but anyways. Now the fact that they tied neutral and ground and the G.F.I. breaker triped is not hard for me to see, but as a test I took the G.F.I breaker out and replaced it with a normal breaker to see if it would still happen and it did.After this I went inside and spent many hours taking things apart and found in two cases where neutral and grond where tied together and seperated them. Things seem to be good now.My question is finally! Once the G.F.I breaker was replaced with a normal one , with all the load in the building turned off, the main breaker was still tripping,the neutral and ground were still tied together in some of the juntion boxes I found at this point. Is it a backfeed that is traveling up the neutral from the main panel that is causing this? Can someone help me SEE THE LIGHT ! I am just not quite sure . I hope I explained myself well enough.
Camp Black Bear