Zigbee light switch with decoupled mode?

I’m planning to do this but still confuse on how to wire the things. I’m kinda new to this one and couldn’t understand on How can the ZB-mini knows if someone interacts with the physical switches but didn’t cut the power off? could someone provide me with a diagram?

Something like this

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So, I only need to connect S2 to the physical switch and I don’t need to connect both S1 and S2 to the physical switch?

Thank you for the prompt response

Either one works

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Houston, we have lift-off!

Aqara finally did it! I managed to get my hands on the Aqara Dual Relay Module T2 and it does exactly everything I could ask of it and more, and to a relatively reasonable price (around 35 EUR or 38 USD where I live). :partying_face: (Disclaimer: I am not sponsored. If I come off as a little bit biased it’s just because I’m happy that I have finally found something that makes my smart home setup work!)

I will still need to perform further tests but I have already confirmed that decoupled mode works. Please let me know if you have any questions and I will try to answer them! I will also create another post in this thread and mark it as a solution and try to update it with any devices that I encounter that meets the requirements specified in this thread.

The following is a short summary of how the T2 fulfills the initial requirements:
:white_check_mark: Use the physical light switch to turn on and off smart bulbs (without toggling the power to the bulb)
:white_check_mark: Use the grid/mains to power said device
:white_check_mark: Use Zigbee standard for said device
:white_check_mark: Not having to rely on bypassing the switch with wiring (edit: added this for clarity)

(and a few extras):
:ballot_box_with_check: Two separate power outputs allowing for control of two lights or devices
:ballot_box_with_check: Supports wet and dry contact modes (this is really neat if you need to control other devices than lights, e.g. garage doors etc. I found a nice explanation here that you might look into if you are interested in this.)
:ballot_box_with_check: In addition to the device, package includes a jumper cable (for switching between dry and wet contact modes) and a DIN rail mount
:ballot_box_with_check: Measures Power (W), Current (A), Energy (kWh), Voltage (V) and Device temperature (°C)
:ballot_box_with_check: Supports interlocking (prevents both relays being on at the same time)

The following possible and confirmed shortcomings are worth mentioning:
:grey_question: The device is a bit larger than my other relays, measuring 45.5 × 48 × 24 mm (1.79 × 1.89 × 0.94 in.). This might not necessarily be a bad thing, but if you like me have small electrical/junction boxes (I think that is the correct term) it might cause issues during installation.
:exclamation: Binding is currently not supported. Hopefully this is something that Aqara can and will add in a future software update.
:exclamation: The device only supports single and off actions for each input ( single_l1 , off_l1 , single_l2 and off_l2 .) When running in decoupled mode the most obvious work-around is to rely on the action (since state is always either on or off), and having built-in support for double and hold actions would make things simpler.

As mentioned previously, please let me know if you have anything you need me to try out (and thank you all for being patient while I was AWOL). :slight_smile:

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Devices that me or other members have reported fulfills the following requirements (post will be updated according to the best of my ability):

In-wall relays:

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I started to read about this topic 3 days ago, bookmarked your post yesterday and finish reading it today to end up on what seems what I was looking for.
Everything was perfectly timed for me :smile:

Thanks @mikaelhertzman for your research and last post :slight_smile:

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Hey, one quick question, since binding is not possible with the T2, is your setup still working when HA or z2mqtt is down ?

I’ve actually thought about writing a post about this. I am looking into redundant measures for if HA/Z2MQTT would become unavailable. Don’t know if it’s possible but my first thought is perhaps having a “cold-spare” MQTT server, configured identical to the one running in HA, that can be turned on in case of emergency.

Even if some of my devices support binding I haven’t really looked into as it seems like it might interfere with scripts, scenes and other logic that I use. I am currently using my light switches for much more than just off and on (even if that is their primary purpose).

After reviewing the T2 further I have found some missing features/drawbacks that I will add to my summary.

I sent the following to Aqara, mainly to confirm that these are missing features but also to suggest that they are added in feature software updates. If you are interested in seeing these features in the future I would recommend contacting Aqara as well.

  1. Is there a reason for why the T2 only supports single_l1 and single_l2 actions? I have an Aqara Wireless Mini Switch that allows for single, double and hold actions wich makes automation so much easier.

    Aqara answers: The current design of the Aqara Dual Relay Module T2 supports single_l1 and single_l2 actions. Your suggestion for additional actions like double and hold is noted, and we’ll forward this to our development team for consideration in future updates.

  2. Is there a reason for why the T2 does not support binding? Some of your devices seem to, but not this one. Binding is a dealbreaker for some smart home users looking into Zigbee relays.

    Aqara answers: The lack of support for binding on the Aqara Dual Relay Module T2 is a design choice. However, we understand its importance, and your feedback will be considered for future product enhancements.

  3. Decoupled mode is great, but what would be even greater is if it was possible to change between decoupled and control_relay for example by pressing the switches for a certain time, or pressing the reset button etc. The reasoning for this is that the decoupled mode is used to a great extent to control smart bulbs. If, however, the Zigbee or MQTT network becomes unavailable you often want to have a way to temporarily fall back to the control_relay mode without having to reset all relays. Think of it as a way to create redundancy.

    Aqara answers: Your idea of having a switchable mode between decoupled and control_relay for redundancy is interesting. We’ll pass this suggestion along to our development team for evaluation.

It might mean some additional considerations, but generally should be OK.

I refuse to have a switch on the wall that doesn’t work intuitively for at least basic functionality with or without HA involved, ie, if I press the switch a light/fan/etc turns on. I will gladly give up some functionality for consistency with this.

Double presses/holds/etc for the more custom actions can be through HA.

ESPHome allows for great customization with or without HA, but unfortunately the compatible switches I’ve tried just look and feel cheap.

I agree. This has sort of become the “holy grail” of many smart home enthusiasts. Smart things that fall back to their non-intelligent origin if things go wrong. With smart solutions, scripts or work-arounds (or even better - manufacturers providing built-in support) my hope is that we don’t have to choose.

I have not yet tested my ideas to accomplish what we are both looking for and even then I am certain that people much smarter than me are also looking into this. Let’s hope someone finds a good solution!

Sounds reasonable. How does one keep the relay/switch from interacting with it’s bound device until we are certain that a double or hold action was or was not performed though? Or perhaps that’s not even an issue? (As I mentioned previously I am pretty new to binding and have to experiment/read on this topic.)

I’m in exactly the same boat as you and have tried many different options.

Do you still require the Aqara Hub for this to work? Or can you just connect straight to a ZigBee controller?

Generally the switch does the interpretation, ie you get either a single, double or hold event. But… I have the luxury of Inovelli switches in the US with dozens of configurable options. Most are not as accommodating.

The relay works without the Aqara Hub.

FWIW I’ve never encountered any Zigbee device that doesn’t connect to Z2MQTT and my CC2652RB (or Conbee II that I previously had for that matter).

Sometimes all options are not available in Z2MQTT, like with the Aqara FP2 Presence Sensor and its zone configuration, but in my experience basic connectivity should work most of the time due to Zigbee being a standard with certain requirements.

I might be wrong, but my feeling is that the warning labels that inform customers that you “need the ” are just a way of promoting products and increasing sales.

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Yeah, as long as the switch can tell the difference between a single, double or hold action it will at least allow for some configuration of the latter two.

What I would really want if I could have anything however is a switch that defaults to controlling the relay if the connection to the MQTT host is unavailable. Binding should still be a default option for all relays in my opinion, but in my case I want to be able to control more than just “off” and “on” with a single press action.

Regarding Inovelli I really wish they would expand to the european market. They seem to know what their customers want.

Agreed about the warning labels, although checking the Blakadder list is a good idea because if there is no quirk (ZHA) or the Z2M equivalent it can be a pain to make automations. Of course, manufacturers will understandably not guarantee stuff that they cannot control, so I understand they will not make a list of hubs that their device works with.

Can you set one input as wet (i.e. lightbulb) and the other as dry (i.e. garage door)? Guessing not.

Just saw a review for the new aqara z1 pro switch and it does include decouple mode

Only see the z1 listed on z2m, the pro version has a gesture button on the left side for dimming control