Neutral Earth Fault

Hi,

ok ok so I tested this old 3036 board a week ago ready to change today, all ok, nothing bad.

went today to change the board, changed it all etc, had to extend two legs, but other than that, nice job.

i go to switch it on prior to testing like you do, and one of the RCDs won't hold.

bugger, what have I done? Scratching head...

tested IR and its 0.02 between neutral and earth, so I think maybe I missed something previously, I quickly removed a few faceplates as there were only 6 sockets on that ring as it happend, nothing obvious.

anyway, so I think I'll try continuity between Earth and neutral at one we of the ring and got 0.61 and did it the other end and it was 0.02, so I think, that's a bit sodding close to the board, what could it be?

so I start t remove that circuit from the board thinking maybe of done something strange with a joint where I'd extended the leg... Nothing.

so I stand back and think what the heck is it, then I think hang on those shelves weren't there before.... Three large oak shelves, in the return on the wall directly sbove the fuse box....

i thought, I wonder... So got the meter out and touched it on a screw head on the bottom shelf and would you sodding believe it I had continuity!!!

anyway, so I removed the screw and it resolved my problem...

Customer later returns home, says everything ok? I said yes, it is now...

i said they are nice shelves, did you fit them? No we had someone do it for us.... I said tell them they drilled through a cable.

thete were probably 8 cables going straight up the wall where he had drilled 3 holes so not sure how he managed to miss the others, luck I say!

anyway...