RCD Fault.

[GJD]

ahh yeah, you're right.. apologies, just saw TT and assumed 100...

ignore me, working nights has frazzled my brain

 

[tony mc]

If you test from the RCD with both the Line & Neutral load side disconnected it has to be either a RCD fault or a tester fault if the coil is not tripping or seeing a imbalance in the flow. As you have already said that a N/E fault was reintroduced IMO the RCD'S are looking a good bet. My way of thinking is that whatever Earthing system the premises has makes no difference re the operation of the RCD the only thing I can see with a TT systems is doing a 5 X test which may fail with a high Ra over 330 ohms which would put the touch voltage over 50 volts and abort the test !

 

[Geoffsd]

Has it been said if the test button works?

 

[bigbaddave]

Test button does work yes on all three that were installed yes

 

[Edd]

disconnect all load, switch RCD on test between L-N on load side and use the neutral on the live side of the RCD as the earth. not the TT earth. Does it trip? Do the same with load connected.