Rcd tripping problem

[ArseyDee]

Mate, I think he means live and neutral. Space bar truoble.

Space bar AND spelling trouble!

.....since edited and corrected!

 

[Braz1845]

This would show up on IR test though,and IR between LNEof this circuit clear!

 

[Octopus]

If its an intermittent trip then the IR tests may show nothing. Time to get your screwdriver out!

 

[gnuuser]

Other option..."someone" has had sockets off entirely and messed up the terminations?
Line/Neutral wire come loose and touching an earthed back box?
Bad socket outlet?

ive run into this before with a cooling fan a neutral shorting against a box.
my poor apprentice had a fit trying to find the fault,
i told him what it was but had him find out where it was
tracked it down to the first junction box on the conduit run.

 

[PEG]

Also,if others have fiddled with socket fronts,especially decorators,don't just check terminations and cable bends,peep right down to see if cores have been pulled,cutting on backbox aperture,EVEN through grommet (if fitted!) They love doing their own version of insulation testing...

 

[Braz1845]

Hi guys here's an update'ive been on site today and done a thorough inspection and found that IR between earth and disconnected neutrals all fine(2 circuits 22 Meg all the others 299

One thing that has come to light is that the over head line has recently been changed to pme or pmb,not sure which .
But the overhead line now has a earth cable running from what I believe to be neutral to an earth electrode,which is about 30 yards from my incomer
Ive checked linked N & E at my supply and all ok,wondered if I was getting some sort of leakage to the suppliers neutral which is connected to an earth electrode in close proximity.
finally the property used to be a TT system and electrode still in the ground but not connected,also water supply in lead I think
oh and I've changed the Proteus RCDS for Hager
So wait and see!!!!!!!!!

 

[Engineer54]

No the overhead supplies PME N-E connection will have no affect on your RCD tripping problem. Depending on the Ra of the existing rod it might be a good idea to reconnect the rod to the MET. Don't bother if the Ra is way over 10 ohms.

22 Meg ohms equates to 22 million ohms, so you don't have a problem there either. So if the problem remains you have more checking and testing to do!!