Yeah it should be in the DIY section I know

Parents have a new house and the previous owners have these god awful ceiling halogen spotlights. Two rows of 4. One wall switch.

They are soooooooo bright that we wanted to change the switch for a dimmer but for the love of me cant work it out.

Two twin core cables coming out the socket. Both with earth, live (brown) and two blue (neutral). Existing switch has live going into L1 and Com , blue are in a choc block. Think the lights are mains so tried to fit a dimmer but if we replace the wires like for like , the lights are on or off, no dimming.

However if we try to use the neutral (blue) wires, the fuse just trips. Switch is rated for 400W.

Is is a case that a) the incorrect dimmer switch b) wiring wrong or c) we are numpties ( i favour the last option )

The switch purchased was this

http://www.diy.com/departments/holde.../940211_BQ.prd

 

Sounds like the lights (probably with transformers?) are non-dimmable to me?

 

ah never thought of that

 

Swap the bulbs out for less powerful LED ones?

 

Not all lamps are dimmable including LEDs. Sounds like the blue is a neutral. Are the spot lights mains 230v gu10 lamp or 12v mr16 lamps. Get a pic up of the switch, lamps used and the lights.

 

Might be the dimmer switch, try the dimmer switch in another room to check functionality of the switch

 

Just need one of these

 

Not so easy when they are miles away , getting on a bit and have as much clue on electrics as I do

I have a feeling given some of the replies on here that the transformers in the ceiling are the non dimmer type and so we might be battling against the odds

 

If it's 12 v then like mentioned not all are dimmable, the transformer. Might be just better off getting a few new fittings with some LEDs, dimmable ones though

 

would it be a big job to a) replace all the lights in the ceiling with LED which can be dimmed or b) remove all ceiling lights and replace with a lovely single pendant complete with frilly lamp shade

I think either job requires access into the ceiling space and could be a big job

 

It's not a big job to change them all to 240Vac GU10s if they are currently 12V transformer MR16 bulbs. I've just completely re-wired my house to mains LED dimmable GU10 holders and bulbs. I would say it's something you might want to do for them though.

 

oh christ yes ! there is no chance I would let them tackle it. there is a higher chance of them blowing the house up, even more than me

 

 

It will trip, as that sounds like a broken live switch, the neutral needs to remain joined.

If you pull the fittings out of the ceiling, you'll know if they're mains or 12V, mains will have one/two lengths of 1.5mm twin and earth terminated on them, 12V will have a far smaller cable going to it attached to a transformer.

 

It's really not a big job to change one fitting to another, if you can gain access to the void above.

 

I'd be amazed if it was 12V to the switch. I'd expect mains at the switch and the transformers somewhere in the ceiling near the lights.