Usage Question - Matching Dimming Levels for 2 devices

I have been able to successfully create automations to match the on/off status of two devices by creating two automations. a) If either Switch 1 or Switch 2 is ON, then turn ON Switch 1 and Switch 2 and b) if either Switch 1 or Switch 2 is OFF, then turn OFF Switch 1 and Switch 2.

Now, I am trying to MATCH the dimming level across both switches. In other words, if Switch 1 is 50%, then Switch 2 is also 50%. If I dim Switch 1, then Switch 2 is also dimmed. I tried to use Automation for this, but somehow the current conditions don’t allow me to dim Switch 2 if Switch 1 is dimmed, etc.

I am trying to stay away from Smart Lighting because it is not supported in all regions, and I’m not sure that this would work there as well.


Smart Lighting has a “sync with switch” feature that does exactly this. If it’s available in your region it would be the simplest solution.

1 Like

Great minds think alike… I just posted a topic this morning on this same issue, but with a slightly more specific use case. :sunglasses:

Virtual 3 way for dimmers?

The only methods I know of for mirroring behavior like this is Association Groups or Smartlighting. Using Routines, you can do something like “If Dimmer 1 is 50% then set Dimmer 2 to 50%”, but that doesn’t create the mirroring effect you want since it only works at that specific dim level.

You might be able to use variables in to create rules like “If Dimmer 1 turns on then set Dimmer 2 to the value of the event data variable that has Dimmer 1’s dim level”.

2023-03-28T18:50:08.748176914+00:00 INFO GE Z-Wave Switch/Dimmer/Fan/Outlet  <ZwaveDevice: 54a6b897-1a57-4153-8211-e12233049cc4 [76] (Guest Bedroom Light)> emitting event: {"attribute_id":"level","capability_id":"switchLevel","component_id":"main","state":{"value":100}}

I still don’t think that gives you the mirroring effect you want if you were to physically change the dim level or do it via the ST app. Someone who is more skilled in Sharptools rules might be able to create rules that can synchronize the behaviors more closely.

1 Like

In my topic, @TapioX posted that there is a way to do this with the rules API, which didn’t meet my use case, but might meet yours.

Thanks, was trying to stay with basic and not involve Smart Lighting (not deployed in all regions). Association Groups are flakey (using the VRCS4) and it involves adding configuration settings to configure the Z-wave device ids.

One thing that I just noticed is that Routines added this new behavior called Dimmer/Matches… and it seems to have broken the old routines – routine 1 turns devices off if any device is turned off; and routine 2 turns devices on if any device is turned on. This no longer seems to work but just debugging right now and so let’s see if it’s me.


Respectfully, zwave association groups have been a solid and reliable technology for 10 years, and are widely used throughout the industry.

If you want to say they are flaky with smartthings, I would believe that. :wink:

But I would bet the exact same devices would work just fine on another Z wave platform.

Just sayin’…

1 Like

Don’t mean to offend. I may be using the VRCS4 outside of their specs (of course, their specs are nowheres to be found), but I couldn’t get them to reliably work. Maybe just me.

But, in any event, my goal is to try to optimize the use of Smartthings and from I have read Scene Controllers and Smartthings are not exactly a match made in heaven (sorry for my snark).

If we take associations aside, the question that you asked in another thread about keeping two switches in sync is appropriate. I expect that this question will be asked for all types of devices and good to see if this can be managed. If for example, I have two dimmer switches that I want to keep in sync, then Associations can’t be a solution unless you write your own driver (I think).

1 Like

To finish the thread, my target devices are Leviton Dimmer Switches. If I try to dim using associations, the device becomes non-responsive. It may be a case of old firmware but surely no place on the Leviton website to see if newer firmware fixes the problem. I can fix the problem by powering off/on via the circuit breaker. I haven’t had the inkling to factory reset the switch as they are embedded and would have to clear the pantry to get access to it.

I expect other people may see the problem which is why I am trying to use Smartthings Automation to work through this and allow me to add non Z-WAVE devices as I move to other technology.

I’m not even sure how we find out the firmware version a device is running without the IDE.

You said at the start you were trying to avoid Smart Lighting/lighting so I didn’t comment. But I’ve been using it to sync dim levels across devices for about 3 years with no issues. I’m only doing this “one way” with a specific device being the controller. I use a virtual dimmer as the controller, controlling multiple real devices.

In case someone turns off the individual devices, I also have a Routine to clean up the state of the virtual device.

And lastly, I’ve got a convenience Alexa Routine set up so it works no matter what devices in the group are actually on (so the virtual device may or may not be on)

So, slightly complicated under the covers but since we mostly use voice assistants, we can just say “Alexa kitchen ceiling 50%” or “Alexa kitchen ceiling off” and it just works.

1 Like

Both @philh30 and @Mariano_Colmenarejo have configuration and/or explorer Edge drivers that can tell you the firmware version for devices.