Help needed on lighting circuit please

[rod1924]

New dual RCD CU fitted today. IR tests ok for circuits up and down albeit UP has only L/N into CU. Put on separate RCD's, down ok but up trips both RCD,s. Tried both in one MCB: Down ok till turning on any up light then RCD trip

Any help really appreciated as brain frazzled

 

[bigbaddave]

Shared Nutural.. Come on really.. You have to ask...

 

[Marvo]

Crossed or borrowed neutral?

 

[Sintra]

Shared neutral most likely suspect.

 

[Dan the spark]

Hi rod, burrowed neutral sounds likely but when u say u tried them both in same mcb and they tripped, had u put the neutrals onto the same bar also?
Id take a look at the landing/hall 2-way as this is normally the culprit, pinch a neutral from the nearest light

 

[GLENNSPARK]

New dual RCD CU fitted today. IR tests ok for circuits up and down albeit UP has only L/N into CU. Put on separate RCD's, down ok but up trips both RCD,s. Tried both in one MCB: Down ok till turning on any up light then RCD trip

Any help really appreciated as brain frazzled

whenever undertaking a C/U change on an install....can you please IR test between the neutrals first to make sure their clear..Thank you.
Glenn.

 

[rod1924]

Thanks for the replies (I knew it was a borrowed neutral) but I am looking on a fix to solve the issue (N were terminated together...answering previous questions).

Last job was the same (borrowed N) but with RCBO's. Using one RCBO solved the issue....and borrowed N stated on Installation Report.

So, any other remedies?

 

[lister101]

So, any other remedies?

5W light bulb might just do it

 

[rattlehead85]

Thanks for the replies (I knew it was a borrowed neutral) but I am looking on a fix to solve the issue (N were terminated together...answering previous questions).

Last job was the same (borrowed N) but with RCBO's. Using one RCBO solved the issue....and borrowed N stated on Installation Report.

So, any other remedies?

What!! You left a potentially dangerous condition in an installation and noted the fact on an EIC? You should have remedied this or at the very least informed the customer and issued a danger notification cert signed by both parties if they refused to get this seen to! at least you would have coveted yourself! Or was this an EICR you was carrying out?

 

[rod1924]

FFS Rattlehead, obviously the client was informed but would not pay for remedial work. Advice sought from my body and all details recorded. But thanks for the advice

 

[GLENNSPARK]

FFS Rattlehead, obviously the client was informed but would not pay for remedial work. Advice sought from my body and all details recorded. But thanks for the advice

well then you slap `em with a danger notice...

 

[bigbaddave]

Thanks for the replies (I knew it was a borrowed neutral) but I am looking on a fix to solve the issue (N were terminated together...answering previous questions).

Last job was the same (borrowed N) but with RCBO's. Using one RCBO solved the issue....and borrowed N stated on Installation Report.

So, any other remedies?

Please tell me this is in your own home?? If its a paying customer id be a tad upset.

As for sorting it. What load is on the two lighting circuits? Either create one circuit if its not going to become overloaded.. or sort your borrowed nutural problem.. Its basically one circuit sharing a nurural from another circuit. Usually the landing light to save running 3 core upstairs..

If you have to ask how that is corrected then i have to question your ability..

You a qualified spark mate?

 

[bigbaddave]

Seems to be a slight contradiction from the OP moving through the posts.. From not having a clue in post one and knowing the fault once told.. Dont try and pull the wool over peoples eyes..

Its so blooming obvious..