Bulb Trips The Circuit

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Borrowed neutral tripping RCD me thinks?

:innocent

If so...

as has been said..

get a "proper" electrician to sort it out.

Unlikely unless there have been some recent modifications we have not been told about.

More likely an actual fault that the incompetent first electrician failed to find.
I still stand by post#6

Whenever anyone comes to a forum asking for advice there is very often been some alteration or changes that are not always fully disclosed in the opening post..

Bog standard IR testing will not show up a borrowed neutral...

As the "fault" path is not from either live or neutral to earth...

And if he's just done a global IR test across Live and Neutral combined to earth then no way he's going to spot it...

Sounds like a 5ww short course Board change to me?

:popcorn

p.s.

Borrowed neutral are not always between lighting circuits...

I've seen plenty of lights getting their neutral from a socket circuit..

(especially in bodger conservatory extension....

Live from the light switch.. neutral back to the nearest socket!!!!!   :shakehead  )

 
I was starting to consider that someone had picked up a neutral from a socket below the switch ;)

Or maybe.... A double switch using the earth as a SW L and picking up a neutral from the socket circuit in the bedrooms..... :eek:

 
I still stand by post#6

Whenever anyone comes to a forum asking for advice there is very often been some alteration or changes that are not always fully disclosed in the opening post..
Yes in this case the alteration was the fitting of the new consumer unit.  How anyone can think that is not relevant and therefore omit to mention it in the OP I just don't know.

 
I am absolutely wowed by the responses here, I just logged on to see if there was a reply and there are loads - BIG thanks to you all.....

We've replaced an old consumer unit with a new double one and when on the old unit this fault was not apparent and using the light didn't trip anything.  Using the light now trips the main RCD.   Yes, testing the circuit proves ok, adding a fitting and socket causes the trip.   I'll get the electrician to read these responses (including the ones that recommend someone else...!!), I also wondered if it was a 'load' thing and if a low 'load drawing' bulb would maybe help..  Please don't have a pop at me, I'm just the client with daft ideas to 'help' who's hoping for a fix... :)

I'll get more info as this thing progresses......

Btw...

Trailer Boy - Electrician. - Electrician has mentioned this could be the case, just not found it yet

Badger... Meters are being used (though I'm not the one that's using it - probably for the best!) - I will keep your offer in mind

IzzyS - I looked for a Forum to see if I could help i.e. getting other input can sometimes help the 'penny drop' and help find another route to a solution, I assure you - it's not me fiddling with the cabled here ;)  

ProDave - Expecations can vary I expect.. I'd like a working light but am realistic that it can take time to find a fault, that's why I am happy to work with the Electrician to help solve the issue in any way I can

Murdoch - Us = Me (Graham) and the Electrician (Frank)

Manator - So using Compost to help bed the bulb into the socket is not recommended then? 

This sentence suggests to me that the spark is non existent. What decent spark would allow a customer to help them change a CU?

Madness

We are not being told the whole story me thinks!

 
Last edited by a moderator:
If someone says "We've put in a new kitchen"  doesn't mean that they helped to actually fit the kitchen.

 
If someone says "We've put in a new kitchen"  doesn't mean that they helped to actually fit the kitchen.
It depends if you take the English language at face value or trust it's adaptation to every day speech.

In true English the phrase "We have put in a new kitchen" does imply that they have assisted in the construction. However these days it is not uncommon for people to say things like "we have had a new extension built" or "we have had a new bathroom fitted" and there are no assumptions on the listener that they have done so themselves.

 
Top