Detached smart wall-switch (EU)

Hardware
1

Hi,
I am seeking advice for a wall switch, but no need for actually switching power (no relay):

  • wifi a must, no zigbee, no RF
  • works with HA of course
  • no 3rd party app required, no 3rd party cloud required, no alexa required, etc
  • no proprietary software: it can run my own software or at the very least an open source software
  • ESP32 a plus since I am a bit familiar with it
  • powered by main (no battery)
    Thanks!
2

All your per-requistes indeed tend to a device with a esp (82xx or 32). I’m not really aware of solutions without relay but as you have control over the *ware running on your wall switch you don’t need to make use of them at all :wink:

Not sure if you are happy with “touch switches” because then you actually have a quite big varierty of devices to choose from.

If you prefer wall switches with “haptic” feedback I can suggest this type here:

The 3-gang version comes with a esp8285, 3 buttons and 4 leds (3 blue ones per button and a central red one) beside obviously having 3 relays. All freely programmable as the owner wishes. :ok_hand:

On the other hand the Sonoff M5 wall switches feature a esp32 but ships with a (probably) sh*tty stock firmware so manual intervention (flashing via serial adapter) is once required to role your own *ware

3

I’ve never tried to setup a Shelly without their app, but I’m not gonna be surprised if that is possible, as after the setup I know you can do everything without their app.

They have a couple of models that are just the sensor, and with a nice integration to Home Assistant:

https://www.shelly.cloud/en-se/products/product-overview/splusi4x1

The i3 model is quite small, so I really like that:

Also, any other Shelly model with a relay can work in detached mode…

4

When you just want to “retro fit” an existing wall switch a (far) cheaper solution (without app :stuck_out_tongue_closed_eyes:) is possible.

I actually turned one of my old “dumb” wall switch into a “smart” one by simply hooking up a $1 esp12 module behind it. The box doesn’t host any AC voltage and 3.3V power source was “harvested” directly from a smart wall switch on the other side of the wall :toolbox:

I also sponsored a $0.10 buzzer :sound: so now that “detached” wall switch also gives a direct feed back in case the command doesn’t reach it’s goal :goal_net:

Still a “real” smart switch can have various advantages like the leds for status and allows multiple actions like single press, double, long etc. which is not possible with “simple” toggle switches and a shelly behind it :bulb:

1 Like
5

Thanks for taking the time: yes i can live with unused relays. I did not know that athom brand and that looks that may fit the bill.

6

Concerning Shelly, i have some installed (1 and 2.5) for real power switching and I am happy with them: I did not consider them because i probably would not have the space for 2. But i did not know about this i3 which is closer to what i need. And when i looked it up i saw they also have a 4 input (i4) version. Thanks!

The ESP12 (or ESP32) is cool when DC power is available but that’s not the case for me.

7

There are really small (and also cheap) AC-DC power supplies which nicely fit in the wall boxes. :pinching_hand:

The very nice ones are quite expensive, like that type here: :money_with_wings:
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But I’m very happy with my cheap Hi-Link based solutions where I pay about $2 for the psu itself and spend another 50 cents on a thermal self reset-able fuse for peace of mind :crossed_fingers:

imageimage

That combined with a esp12 or even a d1 mini will allow to mimic something like this shelly 3/4 input module or even more (and also outputs) for less than 5 bucks :money_mouth_face:

Only thing to keep in mind that the input circuit must be low DC voltage (typically 3-5V when directly attached to the esp gpios). That means you shouldn’t wire any AC wire to a wall switch but instead only use GPIO’s and Ground from the ESP :warning:

8

Good stuff. Thanks!