Replacing 2-Gang Switch with Metal Dimmer

[samwolf]

Hi all,

Have just moved into a new build (3 months old) and want to replace plastic 2-gang switch (I think that's the correct term - 2 switches on 1 wall plate controlling 2 separate fittings?) with a double rotary metal dimmer.

Current backing plate is plastic, so no earth wiring, and wiring to the switch is currently 2 brown wires(presumably live and switched live) to each side of the switch (1 to com, and 1 to L1, and there is also an empty L2 on each side), then with a bridge of brown wire joining the two L1's together. However there are also 4 blue wires and 4 earth wires going into a terminal block (with nothing out of the other side).

Firstly - if I match the brown wiring on the new dimmer to the existing wiring, will this work? (total wattage per light fitting is only 120W, so within dimmer rating).

Secondly - I will need the earth for the new metal switch plate - presumably I can just wire to the opposite side of the one into the terminal block, but how do I check that it's actually connected to an earth block at the other end of the circuit?

Apologies - new to this - if you need more clarity let me know!

Sam.

[jj4091]

Yes you can do it as you propose, if it is a new build I would be amazed if the cpc's are not connected to earth but you can prove it by measuring between live & earth & you should read 230/240v AC approx.

[samwolf]

Great - thanks - will let you know if I have any trouble.