Multiple dimmer switches from one lighting circuit UK

I'm been playing with the Samotech SM323 dimmer module and found it works really well with Hubitat/Alexa/phone etc etc. I've got a single ceiling light circuit (live/switch live) and I want to change out the 1-gang switch for a 3-4 gang unit, and have multiple dimmer modules in there to control other lights in the room (such as smart bulbs etc).

My question is how would I get power to the secondary dimmer modules? I (presumably) can't connect both live & switch live to them as well as they'll control the ceiling lights when they're used. I guess I want to just use them as soft switches so that when they're controlled they trigger a rule which then affects other devices. Has anyone done anything like this? I was wondering if I could just daisy chain the live wire across to the other dimmer modules so they have power but don't physically control anything.

There is allot of infomation needed to determine if what you want is possile. It depends on the wiring in your home and such. If you are not sure you probably should get a electrician to take alook at it.

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What other information do you think is required to determine this?

I'm not sure if my use case is quite the same but I had a scenario with an upstairs light and a downstairs light that both had 2 way switches attached to them.

I knew that if I connected smart switches to both then one of the switches would constantly be disconnected from power whenever the other switch was used.

In the end I replaced one of the dumb switches with a smart switch to control both upstairs and downstairs lights and then removed the other dumb socket and bought a battery powered smart switch (which looked the same as the downstairs switch) to 'slave' it to the mains powered switch.

Yeah, I know exactly what you mean - in my case though I'd need to get a smart dimmer module which is battery operated and fits behind a UK socket plate. I haven't seen one of these before but I'll have a search in case they exist.

You will have to break up things for individual zones. That will require a knowledge of wiring and knowledge of drywall repair or hire professionals. For the lamps, use smart bulbs with zigbee controllers. That way the lamps are always on but the bulb on/off controll is controlled by both the little zigbee controller and by hubitat. This will also allow color changes and what not. So if you have a 4 button controller you can set scenes that you can push a button for or let hubitat control it or both.

Yeah, I agree with the individual zones comment, but what I want to be able to do is have a 4-gang faceplate with four dimmer modules installed. With only one lighting circuit I'm trying to understand what the best way to supply power to the three dimmer modules which will be used to control other devices in the room.

It would be easy enough to use something like a four button controller, but this is far from aesthetically pleasing.

yeah but right now one dimmer is controlling everything directly correct?

Ah - no. Right now one dimmer module is controlling the main lighting circuit. I want to add three other dimmer modules which will control other devices such as a smart bulb. Those dimmer switches will used effectively only as remotes, I'm trying to work out if I can supply power to them by piggybacking the existing lighting circuit. I don't believe I can purchase a remote rotary controller which will fit inside a regular 4-gang UK light fixture.


This is the faceplate I intend to use, each rotary dial needs to have a zigbee-enabled dimmer controller installed behind it. I know the Samotech 323 will fit, but I don't know if it's possible to make them work as if they were a remote.

Ok I would either use Lutron Castea Pico's or Hue Scene controllers. Both can be mounted in a gang... Here is an example. Far left is a pico... Batteries last about 10+ years with regular use,. Aesthetically pleasing :slight_smile: Wiring a smart switch with no load to be used as a controller isn't recommended.

Okay, thanks! I'll go and see if either of those options have a rotary control which could be mounted in the faceplate I want to use.

Wiring a smart switch with no load to be used as a controller isn't recommended.

Thank you for addressing this, it was definitely what I had intended to try doing. Is there a reason this isn't recommended? Are there any devices which you _can _ do this with?

It's load...Switches need them. I don't know anyone else that makes a hard wired scene controller except lutron. They also do not make a rotary dimmer in Caseta or Ra2 (they're kinda ugly) The pico's can be programmed for dimming. So buttons 1 and 5 can be on/off, 2 and 4 for dimming, and 3 (the center) could be used to lets say close the garage door.

Ah, gotcha. Thank you for taking the time to respond to this, I'll have to carry on with some research. The two products you mention aren't going to mount behind the faceplate I want to use or work with a rotary dial which is a shame - I'm not going to give up on this just yet but I'll keep that as a suggestion in case I run out of other options :+1:

Why not just get rid of the rotary dial and switch the entire plate to decora style? In my pic the second switch from the left is a dimmer. The last 3 are on/off switches.

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With respect to cutting a bigger hole in a wall just to have that, then I agree 1000% - I would never do it. I'd use a Pico or Zen34 instead, no doubt.

But if you happen to have an unused/open gang in an existing box, then it's game on.

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Because the rotary dial is made from really nice materials which feel great to use and are heavily stylised. Obviously beauty is heavily subjective, but I'm really trying to avoid having white plastic stuck to the wall as it'll look jarring in a house that's 120+ years old. I'm doing my best to keep the smarthome stuff invisible and just have regular interfaces that everyone would be familiar with.

Not saying I'm going to be able to get exactly what I want, but I'm willing to explore every avenue! :slight_smile:

To be fair, there's pretty heavy renovation work going on, so making a backbox a little larger is a very minor inconvenience compared to everything else, I'll definitely have room to fit more dimmer modules.

Ahh that will be very difficult. Most smart home stuff will be more modern looking, and in the case of switches most are decora style. (The exception to this is ge/jasco has flip on/off switches in their line)

Absolutely, I'm currently using the Samotech SM323 as an invisible "fit behind the backplate" solution and it's spot on. Visually, you'd never know it's there, it functions like a regular non-smart dimmer and I can also use my phone/Alexa etc etc to control the lights. I just need to figure out how to do it several more times without a dedicated lighting circuit... :grimacing: