RCD Tripping

[angusbrooks]

Hi - I have a CU with a RCD that is working inline with the downstairs sockets and lighting circuit and a separate RCD that works inline with upstairs sockets and lighting circuit.

Prior the RCDs were faulty and trippy replaced both and now the replaced downstairs RCD is not working - when pressing the test button it does not trip out!! When putting power & lighting circuit on ( at MCB ) it does not trip immediate buy trips after a short time and on other occasions it has been known to not trip for weeks?!

I replaced an old edison screw lamp and it has not tripped since - has the problem been resolved?! Should I replace the RCD?! Could someone please advise!

Thanks very much people!

Angus

 

[NozSpark]

TBH it's very doubtful that changing a lamp will have made any difference.

Have you done any testing of the RCD or the circuits that they supply?

Just because a RCD is tripping does not mean that the RCD is faulty,, you may have a very legitamate and real fault on one or more of the circuits that it is protecting.

 

[Badger]

sounds like it could be a neutral to earth fault dead short as i have come across a dead short n-e fault before and the rcd wouldnt trip on test button or meter but did randomly trip out on the 2 occations i was working there on the burglar alarm. have you insulation resistance metered the circuits any alterations been made?