Rcd tripping on downlights

[cliffed]

Been called into a job,electrician who started to find the fault,left & said he couldn’t find the fault,leaving the client running extension leads everywhere for lights,even in the bathroom.
Basically for what ever reason the rcbo trips ,it can be reset but trips again.
It’s a bungalow with joint boxes for the lights,& loads of fibreglass.Ive split the circuit so now half of the lights are on,but kitchen & diner are off.
The M ohm resistance of the faulty cable is L - E,N - E 0.09,L- N 6.90,
No idea why this cable is at fault,managed to get to all lights,they seem ok,not ideally terminated but looks ok.
Later today will try & get to switches & megger as I go along,the baffling thing,is that this fault is happening ,it a nightmare.

 

[Pete999]

Oh was that what he on about? Lol I did not read that far back. It is boxing day and a few wines

Lightweight

 

[Mark Chancellor]

Lightweight

I am qualified level 3 with NICEIC

Trouble is people need to understand that RCD trips under an imbalance in the circuit for example some touching a live conductor.

But MCB'S trip under short circuit or overload

I guess the water conductivity acts as a bridge between the live and either neutral and earth.

Too many sparkies jump straight to testing rather than inspection first and even isolating the problem by visualising.

Yes I am a lightweight one bottle of wine and I'm knackered lol. Have a good boxing day

 

[Pete999]

I am qualified level 3 with NICEIC

Trouble is people need to understand that RCD trips under an imbalance in the circuit for example some touching a live conductor.

But MCB'S trip under short circuit or overload

I guess the water conductivity acts as a bridge between the live and either neutral and earth.

Too many sparkies jump straight to testing rather than inspection first and even isolating the problem by visualising.

Yes I am a lightweight one bottle of wine and I'm knackered lol. Have a good boxing day

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