Advice please!

[SS87]

problem is on a an upstairs lighting circuit, rcbo wouldn't hold. even after splitting circuit down to just the first light it trips as soon as the light is switched on. interconnected neutral i thought...its not, somewhere along the first leg of the circuit is a connection but neutral and cpc have been cross connected. so at the cu i have the neutral return through the cpc to the earth bar. Now this house has just been decorated throughout, new carpets etc, so is replacing this first leg my only option or can i re-sleeve the conductors and connect them to the correct bars. obviously this means neutral will be 1.0 instead of 1.5. ??

 

[Moses]

problem is on a an upstairs lighting circuit, rcbo wouldn't hold. even after splitting circuit down to just the first light it trips as soon as the light is switched on. interconnected neutral i thought...its not, somewhere along the first leg of the circuit is a connection but neutral and cpc have been cross connected. so at the cu i have the neutral return through the cpc to the earth bar. Now this house has just been decorated throughout, new carpets etc, so is replacing this first leg my only option or can i re-sleeve the conductors and connect them to the correct bars. obviously this means neutral will be 1.0 instead of 1.5. ??

Neutral needs to be double insulated.

So if someone has used a connector and cross connected the N&E then you need to replace the cable.

 

[Rockingit]

It's generally considered a big no-no to use the cpc in T&E for anything other than that. I'm sure others will reel off the regs numbers.

Good luck!!

 

[swparksey]

It's generally considered a big no-no to use the cpc in T&E for anything other than that. I'm sure others will reel off the regs numbers.

Good luck!!

WIthout heading out in the rain to the Van
514.4.2
Green Book

I think?

But a big No-No from me too !

 

[SS87]

Thanks for the swift replies, i thought as much regarding replacing the leg. just cant see how or who managed such and obvious mistake. its an ex council house and looks like it was rewired to the 16th regs.

 

[Moses]

Thanks for the swift replies, i thought as much regarding replacing the leg. just cant see how or who managed such and obvious mistake. its an ex council house and looks like it was rewired to the 16th regs.

Some DIY.

 

[swparksey]

Yes more than likely a DIYer
Or a council electrician ONLY JOKING

 

[telectrix]

or a plumber!

 

[snowhead]

Are you sure your "first leg" really is that and there isn't another lighting point with the crossover in it?

 

[Moses]

Are you sure your "first leg" really is that and there isn't another lighting point with the crossover in it?

good point.

 

[SS87]

From what i can see it is, ive traced the cable through the loft so know the route up there and cant see anything else it could be connected to. no outside lights or anything else i can see although it does take a strange route up stairs, from the loft it goes does down the front wall of the house rather than up in the airing cupboard with the shower and smokes which would be the shortest and easiest route (and the one ill be taking). looks like ill be fishing around with my cable rods tomorrow.

 

[diditrain]

Was the RCBO already in place or have you recently tried fitting it?

 

[Deleted member 9648]

Have you IR tested the cable?...are you sure this is not a N-E fault?....seems highly improbable that the cpc and N have been mixed up.

 

[needasparks]

You say it has smoke detectors, can this supply be also used for lighting as a way round damage to decor. Just a thought.

 

[SS87]

thanks for the help and suggestions, snowhead had it right, after a fresh look this morning found one downstairs light was on with the upstairs circuit and the cross connection within.