Electrical question...Can I use neutral from socket??

Deep_Ocean

Hi,

Just a quick electrical question. I installed some lights under my stairs running a switched live from my nearest switch. However there is no neutral to pick up from the switch so I ran a cable from my socket and picked a neutral up from there. However when I switch the lights on it trips the ring main fuse at the board. I assumed that as all the neutrals are connected together at the board it should be okay to pick up a neutral from the socket.

Thanks in advance for any advice.

dave82_2

Call a sparky before you hurt yourself!

markdavey

dave82 wrote: »

Call a sparky before you hurt yourself!

+1 to the above

ic

Have you also picked up an earth from a near by central heating pipe? :eek:

gas4you

Can you clarify what is tripping? mcb or RCD?

zax47

Deep_Ocean wrote: »

Hi,

Just a quick electrical question. I installed some lights under my stairs running a switched live from my nearest switch. However there is no neutral to pick up from the switch so I ran a cable from my socket and picked a neutral up from there. However when I switch the lights on it trips the ring main fuse at the board. I assumed that as all the neutrals are connected together at the board it should be okay to pick up a neutral from the socket.

Thanks in advance for any advice.

OMG! So very, very, very wrong. Never assume, it will make an !!! of U and ME! Leave it unless you have a clue what you are doing.

As an electrician, I'd have added an FCU ("fused spur") from the nearest socket, fused it to 3A and run the lights from that - that's the CORRECT way to do it.

1. You can't "borrow" neutrals willy-nilly from another circuit regardless of their interconnection back at the CU. You unbalance that circuit every time you switch it on - which results in the RCD protecting it tripping as the live and neutral "halves" are now carrying differing currents.

2. Why did you pick the switched live anyway - you needed a live feed from the lighting circuit, not a switched live one.

3. Where have you taken your earth from, or haven't you bothered?

Part P was introduced to protect people from people like you and your dodgy DIY bodges... {"what's that" I hear you ask :mad:}

Deep_Ocean

It is the RCD which is tripping (not the main switch). I will install a fuse spur and come off there instead, I didn't think it would cause a problem to pick a neutral up from elsewhere. As I say they are all connected together at the board so why would it hurt to come off the socket. Obviously from the response that I have received you can't use the socket neutral but could somebody clarify why? Just to satisfy my curiosity. I will use a fuse spur instead, it won't be a problem but I am interested into the reason why it is tripping. If all the neutrals are interconnected anyway why is it tripping? Thanks for above responses

dave82_2

You are probably taking a live from one RCD and neutral from another or the non-RCD side so the RCD thinks there is a current leak and trips. But seriously mate it isn't worth messing around with this stuff. If you are curious get a sparky to come and explain as he does the job.

Deep_Ocean

zax47 wrote: »

OMG! So very, very, very wrong. Never assume, it will make an !!! of U and ME! Leave it unless you have a clue what you are doing.

As an electrician, I'd have added an FCU ("fused spur") from the nearest socket, fused it to 3A and run the lights from that - that's the CORRECT way to do it.

1. You can't "borrow" neutrals willy-nilly from another circuit regardless of their interconnection back at the CU. You unbalance that circuit every time you switch it on - which results in the RCD protecting it tripping as the live and neutral "halves" are now carrying differing currents.

2. Why did you pick the switched live anyway - you needed a live feed from the lighting circuit, not a switched live one.

Part P was introduced to protect people from people like you and your dodgy DIY bodges... {"what's that" I hear you ask :mad:}

That explains my query. Thanks I served an electrical apprenticeship when I left school about 15 years ago and I did qualify :rotfl: Needless to say I am no longer an electrician.

I pulled a cable from a dual switch and swapped it with a 3 way. There was already a live in there. So that is why I have a switched live.

I will take your advice and use a fuse spur, I assume that I can still run the load live through the switch though, so I don't need a switched fuse spur, I can still switch with the 3 gang? (Constructive advice appreciated)

zax47

Deep_Ocean wrote: »

It is the RCD which is tripping (not the main switch). I will install a fuse spur and come off there instead, I didn't think it would cause a problem to pick a neutral up from elsewhere. As I say they are all connected together at the board so why would it hurt to come off the socket. Obviously from the response that I have received you can't use the socket neutral but could somebody clarify why? Just to satisfy my curiosity. I will use a fuse spur instead, it won't be a problem but I am interested into the reason why it is tripping. If all the neutrals are interconnected anyway why is it tripping? Thanks for above responses

RCD looks for the same current flowing in the live and neutral connected to it = RCD happy. If you then shove current down it's connected neutral from somewhere else (as you have done) then there is an inbalance so RCD= unhappy and trips. In your case the current will flow through the lighting RCD live and back down the socket circuit RCD. Any guess which one trips first.

Naf

Please, don't give the OP advice on what they need to do to it, just keep +1 to the original reply for what they need to do about it.

CALL IN A PROFESSIONAL