Lights Tripping Out After New Plastering?!

[jagillham]

Hi all,

We've had the kitchen replastered over the last 2 days and now the lights are tripping out.

Day 1 - Kitchen light comes off and builders have done something that keeps all the wires there safe. All the boarding etc is done this day.
Day 2 - Some point throughout the day it all trips out. No changes done etc. It is the kitchen light that is the problem as when the wires are splayed out (first pic) it does not trip. The second pic is how it was when builders took it off apparently.

Any ideas?

Thanks

James

 

[PrenticeBoyofDerry]

Some point through the day, but not immediately?
Was it a MCB that tripped or an RCD/RCBO/RCCB?
If RCD/RCBO/RCCB, did trip take place whilst lights on or off?

 

[viewer]

When you say that it tripped on the second day:
Was anything connected to those wires?
What tripped?
Was the lighting circuit power on (a RCD can trip without the circuit being on if those wires were touching)?

 

[jagillham]

Hi,

Lights off I assume. We were out, came home to find the upstairs sockets and downstairs lights not working. Our consumer unit was fitted in May this year, so is one with two different RCD protected curcuits.

All the boarding and boxing happened yesterday, so I'd have thought if a cable had been screwed through or something it would have tripped yesterday. Just skimming done today.

Does the wiring for the light seem right? Also what does it mean when the wires are loose like in the picture and do not trip? Its stopped us being plunged into darkness...but im not keen on them lives wires hanging there

 

[jagillham]

My 1st reply was before I saw the 2nd reply. Think I've covered everything except nothing was connected to it during day, except to itself. Not sure how that was done I'm afraid.

 

[PrenticeBoyofDerry]

Hi,
Does the wiring for the light seem right?

The wiring doesn't look incorrect!

Also what does it mean when the wires are loose like in the picture and do not trip?

It means what ever was causing the fault, stops when the cables are separated, but that does not help you any.

It could well be when the cables are reconnected the fault is reintroduced.
Don't rule out it being a damaged cable, sometimes the fault is not apparent immediately, but could also be moisture from plastering.
Did it trip only once or on several occasions?

 

[jagillham]

It instantly trips when connected up now. I did then hook up the light as per the diagram on the wiki here which tripped again, regardless of if switch is on or off.

 

[PrenticeBoyofDerry]

Both browns together, with nothing else connected.
Blue to neutral side of lamp.
Blue sleeved brown to live side of lamp.
Unless someone has been messing with the blues!
Earth to earth terminal.
Do you have an approved voltage indicator?
Out of interest, your picture seems to display a third set of cables, or is it an optical illusion?

 

[jagillham]

Yeh thats what I did, still tripped

Third wire is to run a second light down the other end of the kitchen. Cable has been run to the locations, nothing has been done with it as yet.

 

[DetlefSchmitz]

Damp in the switch. I take it the switch is also on the plastered wall?

 

[PrenticeBoyofDerry]

First thing would be to confirm the blue (sleeved brown) is switch live, so you need a means of testing for voltage.
If you can confirm this it would help.
It may be worth linking the switch out, this may eliminate the area of the fault, then would be down to investigating at the switch and an insulation resistance test on the switch line.

 

[jagillham]

Yeh that's right. Its a metal switch, earth runs to the backbox.

Any way to test?

 

[PrenticeBoyofDerry]

Yeh that's right. Its a metal switch, earth runs to the backbox.

Any way to test?

Best method would be to remove metal switch and replace with another as a temp measure, until switch has dried out.

 

[jagillham]

I've not got plastic to swap out tonight. The wires as they are, they safe?

 

[PrenticeBoyofDerry]

I've not got plastic to swap out tonight. The wires as they are, they safe?

Ideally want to be terminated within an enclosure, so no accidental contact can be made.