Replacing a light switch dimmer module

25 Nov 2020
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United Kingdom

We have a 3 button light switch in my kitchen. 2 of the switchers are dimmers controlling ceiling LED spots, and the other is just an on/off switch for under cabinet lights.

One of the dimmer switches is broken (it will only turn on if you press really hard and ping it out a couple of times). Looking inside, the dimmer switches are BG DM400AP modules ( ).

Is replacing one of these dimmer modules straightforward, and am I (not a qualified eletrician) allowed to change it?
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Usually easy to do and yes you are allowed.
They are good dimmers i have them myself and work well with led.
Ensure the power is off and note what wires and colours go where before taking off, even on the other two switches, take pictures if possible, being a 3 gang there will be a lot of wires so if wary dont try.
There may be numerous wires of the same colour, but each has different purpose, so important you mark whats what.
Likely only two terminals on use on the dimmer your changing
You will likely need 4mm screwdriver for the plate and a 3mm for the Terminals, plus a pair of pliers

Isolate power, remove plate from wall.
Pull the knob off,
To release the dimmer you need to turn the metal ring, without the tool, carefully use a pair of pliars, but try not to scratch the surface of the plate.
A good tip is mask up the plate with tape around the nut bit so if you slip you dont damage the finish

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