fitting dimmer switch

[kokoshka]

I'm fitting a dimmer switch in the kitchen for under cupboard lights. The supply is independent of other lighting circuits, I've picked up from a spur switch that previously supplied the boiler, now re-located. So I have my twin and earth coming in from the spur, a twin and earth heading off to the lights, and a dimmer with three terminals marked 'C', L1 and L2. How do I wire up please?

 

[fireman22]

i take it you have two cables, 2 reds 2 blacks 2 earths.
put both blacks together in a connector block
put both earths together in a connector block with flying lead onto switch and back box if they are metal.
feed red into terminal C
Other red into L1
job done

 

[delmel]

Which type of under kitchen lights have you got, not all are able to be dimmed

 

[kokoshka]

Thanks Fireman 22 for your reply. Delmel, I am using low voltage lights with a dimmable transformer. One more question...I asked an electrician if I could pick up from the fused spur to supply a twin socket as well as my lights. He confirmed that the cable in and out of the spur was mains, although it is on an independent 'central heating' supply, (it has it's own trip in the consumer unit). He told me to treat the 'back' of the switched spur as a connecting block, and to run my new socket spur from there, unswitched. Then I should run my lights off the load, or switched side of the fused spur. The problem is the amount of wires into too little space, mains in and out, new spur in and out, and lights in and out. Since the lights don't need to be fuse controlled at this point, would I not be better off using a big 30 amp junction box with much more space for the wires?

 

[fireman22]

yes, if its on its own way in the circuit board and its 2.5mm cable you can put it on a 20 Amp fuse or breaker.
use a 30 Amp junction box to split cable one cable to socket, one cable to spur for lights. spur feeding lights should have 5 Amp fuse in it.
you could obviously use a 20 Amp junction but as you say there is more room in a 30 Amp.

 

[kokoshka]

``````Thanks again Fireman 22. At the risk of sounding pedantic, but obviously I want to get this right, I can run my mains cable into a junction box, eliminating the fused spur, run a cable from the junction box to the new socket spur, and another cable to the lights but incorporating a 5 amp fuse? How would it be best to add the 5 amp fuse?

 

[plugwash]

if you just wanted a normal switch i'd say use a fcu as the lightswitch

but since you wan't a dimmer you can't do this your options are

1: use an unswitched fcu and seperate dimmer
2: (neater but more expensive) use a grid system like mk's grid plus and fit a dimmer module and a fuse module