New kitchen spotlights working until fitted to anchoring point - sorted

red_imps_2003

Am fitting the 'Kapista' row of four spotlights in my kitchen but am having problems. Having wired it up, all four lights come on and off as they should while the unit is hanging from the ceiling. When screw it into the fixing point on the ceiling, though, it trips one of the two main RCDs on the consumer unit (regardless of whether the light switch is in the on position or the off position) and I can't reset the switch until I unscrew the unit and pull it clear of the fixing point. To be clear, it doesn't trip the switch responsible for isolating the lighting circuit; it's one of the main RCDs so several sets of plugs are rendered inoperative too.

I can't fathom what could be causing this. The previous light (two fluorescent tubes) worked and, as I say, these new spotlights work wile dangling. There is something about affixing the metal rose to to the metal bar screwed into the ceiling that is causing a short circuit somewhere.

I've added the sister set of three (same wiring and fixing setup) at the other end of the kitchen and that seems to be working fine.

I'm waiting on a call back from an electrician but wondered whether anybody has any thoughts of a likely cause in the meantime? I am fairly confident the cause is local to this light fitting rather than being a random fault elsewhere in the house's wiring.

Edit. It looks as though the issue is not with the rose touching the mounting bar fixed to the ceiling per se. I can 'hold' it in place with a wooden spoon and the RCD doesn't trip. It must be something to do with either twisting it those few millimetres to click it in place or tightening the screws (i.e. one of them is touching something as it screws further into the rose. The former seems most likely, as I think it does it even without tightening the screws. It's looking as though this is an issue that requires close-up inspection and probably beyond the realms of remote assistance.

Edit 2: Sorted it. Turned out to be as simple as one of the wires (one of the live ones) was loose. Apologies for wasting anybody's time.