Earth to neutral fault????

[wrf12345]

Hi, I have an old style fusebox and planning to replace (via electrician) with a modern one (wiring was uprgaded by previous owner) and I noticed when removing a spur line to the outside that was not going to pass muster that my multimeter was showing that earth and neutral were connected. I checked some other sockets and lights, same thing, which I guess you would expect as neutral wires are attached to the same plate in the fusebox. When I switched the fusebox off the connection between earth and neutral disappeared so the problem seems either in the fusebox or just the mains supply, as I believe neutral and earth are somehow bonded on some systems? Just wondering if I have a problem or not? House was built in 1955.

 

[johntheo]

I still figure that 2+2=4 Tim, when my double pole RCD is tripped and with a healthy system I get infinity between N & E (my side) and I get a very very small resistance when the RCD is closed (practically 0) . I just checked it out there now. When I had the fault I was getting practically 0 resistance with the RCD tripped and I couldn't reset it until it went to infinity.

 

[timhoward]

I still figure that 2+2=4 Tim, when my double pole RCD is tripped and with a healthy system I get infinity between N & E (my side) and I get a very very small resistance when the RCD is closed (practically 0) . I just checked it out there now. When I had the fault I was getting practically 0 resistance with the RCD tripped and I couldn't reset it until it went to infinity.

My apologies, yes, I see you meant on the load side of the rcd now.

 

[static zap]

By definition , If N gets joined to E after an RCD it will trip.

( without a diagram of what has been ruled out .. we all get confused !)
..detecting small AC voltages present on Earthed things ..can upset some simple
OHMS measurements.
Hence the interest in low current AC clamp meters.

 

[johntheo]

It will, but only if there's a L to E fault (leakage) or a N to E fault on the consumer side?. I was getting a full short between N & E with RCD tripped at different periods for ~ 3 hours, the mystery is why it was coming and going and then disappeared "for ever".