trip rrip trip rcd. hellllllp

[m25maintenance]

big old 3 story town house. 3 cu all over the place. replaced top floor cu. 4 ways. tripping on lights. found polish builders connected a socket circuit onto light circuit on an extention. fixed that problem. guys on lighting circuit runs lights on halls and stairs on all floors. rcd tripping. iv got 20 ohms resistance line neutral . failing insulation test line neu. iv searched all places for connected equipment. lights are brought to switches with line going tru switch neu connector block. could it b an earth line fault. the place is old. wooden back boxes some switches. im thinking there might be a transformer burried somwhere. tanx.o yes as soon as i put lamp in and flik switch the rcd popps.

 

[nickblake]

Ill be honest that doesnt half sound like a borrowed neutral, trips under load , whats the IR between n and cpc , if you have 3 CDU's some where these are linked , that sounds like a night mare job ,wooden back boxes any VIR in there

 

[m25maintenance]

yea boro neutral was my thoughts but the place is so messed up im thinking of walking. the whole place is falling down. polish asses burried loads of junction boxes in plastered walls. who wud connect a power circuit to a lighting circuit 50 years + old with no cpc. idiots,

 

[nickblake]

oh man think changing the board has opened a can of worms there , bang head against a wall springs to mind all i can suggest is see if you can locate the borrowed neutral get the CDU youve changed so they cant come back on you , realy by what you have said it sounds like it needs a rewire just to sort it out ,as you have said crossed circuits , it could be well still that switch all the breakers off and see if you have a live MCB back feeding from one of the other CDU's

 

[m25maintenance]

o tanx thats a good point. but when i iso the cu it seems dead. i get dc light on my voltage indicator. to b honest the whole place is a mess. i might just kill off that circuit and put temp lighting in the effected areas and wait till the full house overhaul gets going