Under Cabinet Lights Tripping RCD!

[barera]

Was called out to a tripping rcd today. narrowed it down to the kitchen under cabinet lights similar to these:

http://www.tlc-direct.co.uk/Products/LLM16W.html

As soon as I connect the fly leads to any of these undercabinet lights (there are 4 in total) the RCD trips!?!

Any ideas/solutions?

 

[Lectrician]

Dumb ass kichen fitter connected the fittings between the socket circuit and the lighting circuit?

You don't give much info.

Switched by an FCU or light switch? Which circuit are they on? Is this circuit on the RCD side of the board? Is it a split board?

 

[barera]

Split board, switched through FCU, on RCD side, on Socket circuit.

 

[EdwardCurrent]

Hello,

So, with all the lights unplugged, you can switch the FCU 'on' and you have a live 'fly lead', no problems ?????

Ed.

 

[bernardgreen]

Has the fitter connected the fly lead to Live and Earth in the FCU instead of Live and Neutral ?

 

[jj4091]

Does the same thing happen if you connect them & use the built in switches to isolate/switch them on?

 

[Roo]

Got the same lights under my cupboards connected to a FCU on RCD protected ring.

When I've got the cooker,TV and these lights on my RCD trips also, not straight away tho usually last good 30mins.

Without cooker or tv on their fine.

Told mrs not to use them now anyway and I've removed fuse from FCU.

Have looked at FCU tho and everythings tight and in the right place.

Only really used them at partys anyway so people could see what drink their getting so hasn't bothered me much.

 

[securespark]

I often find the switched live for these comes from an existing switch (on the non RCD side of the board) and the neutral (as someone said earlier) from an adjacent s/o.

Or if you have a PME supply, you can get odd faults affecting the RCD. Sometimes these faults are on the other side of the board.

I had a split-load RCD tripping on a PME supply when a security light was switched on (on the non-RCD side!!)

Turned out to be an NE fault on a ring final.....

 

[barera]

Yes Edward, that is indeed the case with FCU switched on the fly leads are live without any problems until I plug any of the fly leads to a fitting, then the RCD trips! And as we all know the fly leads have no cpc only fase and neutral in them!

 

[barera]

Bernard the fly leads are connected correctly to Live and Neutral Not to Live and Earth!

 

[barera]

JJ, I havent tried that. will try it tomorrow when I return to the site!

 

[jj4091]

To be honest these fittings are more trouble than they are worth, in my opinion & I have never had any long lasting success with them. I swapped all ours for low wattage L.V. cabinet down lighters with transformers.