3-way setup with two LZW31-SN dimmers in HA in endless loop

I’m trying to get a 3-way setup with two LZW31-SN dimmers switches working. Being able to dim at both ends of a 3-way without “must go through the hub” lag and have both switches stay in sync isn’t asking too much, right? :slight_smile:

First the setup:

Wiring:

  • Followed the wiring example from this youtube video. Diagram is at 1:04.
  • Opted for the 2-way “mirroring” option with dimmers since lag was 10+ seconds at times using automations going through HA and it just seems janky.
  • This sort of use case seems to be exactly what ZWave groups and direct node to node associations are for.
  • The video suggests disabling the internal relay (Hit Config A button 8x) but I had to leave it enabled to get this far.

Setup in HA:

  • Master dimmer added to group 3 of slave dimmer
  • Slave dimmer added to group 3 of master dimmer
  • group3 explained straight from Inovelli’s Zwave compliance doc - https://products.z-wavealliance.org/products/3438/embedpics: Switch Multilevel Set Group 3 can be used to keep the, “master” switch in sync with the “slave switches”

The problem:
Both switches stay in sync with each other but they end up in an endless loop of sending the same command (due to the 2-way association) to each other which just isn’t going to work. I can see this constant repeating of the same command back and forth by tailing the OZW log file.

Anyone have any suggestions?

Have you tried

  • Master dimmer added to group 2 of slave dimmer
  • Slave dimmer added to group 3 of master dimmer

I dont think group 2 is kept in sync (it is just basic set commands). This way anything you do on the master switch will be sent to the slave switch to keep it in sync, but the slave switch will not forward it back to the master. Anything you do on the Slave switch will be sent to the master switch, and the master switch will send it back to the slave switch once, but it will end there.

3 Likes

That did the trick! I don’t know how long it would have taken for me to figure that out, but you just saved me quite a bit of hair pulling. Thank you!

There is one small annoyance, but it is pretty minor IMO. Controlling the slave switch remotely via HA doesn’t work, but that just means always using the master for remote control in HA and not using the slave which is fine by me.

I have almost the exact same setup and have the two switches slaved to each other via group association. In the HA z-wave configuration tool (Configuration->Z-Wave) I selected the dummy/aux switch (the one without load) and grouped both group 2 and group 4 to the load switch. This association is one way (Aux switch sends to load switch), otherwise, I think you would get the result you are talking about.

This is working well for me.

As a kicker, I wrote this node red subflow to keep the LED bars in sync and your post inspired me to share it: Home Assistant Node Red Sync Multiple Dimmer LEDs Subflow Code

Here is my config:
47%20AM
16%20AM 04%20AM

I just want to follow up here for the benefit of others to share my final config.

It is possible to have two Inovelli Dimmers in a 3-way setup dim at both ends and keep everything in sync (on/off state and LED bar on both dimmers) with ZERO additional automations/hacks in HA.

I think the wiring setup I used is crucial.

  • Master dimmer added to group 2 and group 4 of slave dimmer
  • Slave dimmer added to group 3 of master dimmer

Stay sane!

4 Likes

Cool - I will give that a shot and see if I can move away from the HA solution.

This needs to be added to some official documentation. Such a lifesaver!

I later found out that there is a config parameter for this very thing: Parameter 12 (Association Behavior). Setting this value to 11 on your slave dimmer will prevent it from creating an endless loop.

value description
01 local
02 3way
03 3way & local
04 z-wave hub
05 z-wave hub & local
06 z-wave hub & 3-way
07 z-wave hub & local & 3way
08 timer
09 timer & local
10 timer & 3-way
11 timer & 3-way & local
12 timer & z-wave hub
13 timer & z-wave hub & local
14 timer & z-wave hub & 3-way
15 all
1 Like

I want to report that Thanks to this thread I got 2 LZW31-SN switches working in a 3-way setup. I wired them as suggested in the article.

Then using the zwave association tool, I sent group 2 and group 4 from the non-load switch as source. The dimmer and on/off work from both switches. I sent group 3 in the opposite direction. The light bars match up on both switches. A quick note, I did not disable local or remote control on either switch.

Sometimes there is a sleight, but mostly negligible delay. But if it shows up, it’s really not that bad and I’m quite happy that these are working together.

I had no issues with a feedback loop. I am using smartthings hub though.