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2 gang dimmer wiring to replace old 2 gang switch

Postby The Latch Key Kid » Fri Aug 20, 2021 9:15 pm

I have an old 2 gang switch that has 1 com that is bridged and then 3 other wires that are L1 L2 and L3. My new smart dimmer switch has 2 cross lines which I presume are for permanent live and then 1 for live and 1 for neutral. Can somebody help me please? My pics are too large to upload. There are 2 blocks on my old switch. The ones with com at the bottom and L1 and L2 at the top. 1 red wire is in the bottom com with a bridge to the other bottom com. Then on the first block I have a black wire in L1 and nothing in L2 and on the other block I have a red wire in L1 and a black in L2. My new switch has X L N X
The Latch Key Kid
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Postby ericmark » Sun Aug 22, 2021 12:40 pm

I think the X is really [attachment=0]Dimmer-termial-sign.jpg[/attachment] and it is output to lamps, so in to L out from [attachment=0]Dimmer-termial-sign.jpg[/attachment] normally we only have Com and L1 or L1 and L2 with an on/off switch, we may get Com L1 and L2 on a two way switch but the dimmer is not two way.

You can get two way dimmer switches they come as a pair you can't mix and match with other makes.

Electronic switches without a neutral have to allow a small current through the switch when off, so some bulb will flash when switched off with a electronic switch without a neutral, also some bulbs will shimmer when switches on, and only way to find out is try the bulb, so using smart bulbs is often the easiest way.
Dimmer-termial-sign.jpg (28.28 KiB) Viewed 129 times
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Postby The Latch Key Kid » Sun Aug 22, 2021 2:07 pm

Thank you for the reply. This is a 2 way switch. You can connect lightwave rf dimmers through the app. I have wired the switch up now, thanks to your explanation. I have the common in L and a black wire from L1 in one switched live and the red wire from the other L1 in the other switched live. The switches work fine but for some reason there is now zero power going to the switch upstairs. I am guessing that the black wire that used to be in L2 along with the red L1 is feeding power to the upstairs switch, but I have nowhere to put it, do you know where it should go?
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