Shelly 2.5 to a two wire motor 24 v

I’m trying to exchange a 433 mHz controller for my window opener running at 24 v with a shell 2.5.
The problem is that the controller needs to output +24v or -24v to either open or close the window.

I thought I could do this with a shelly 2.5 but I can only have +24 on one set of wires(N + O1) and +24 and a other set of wires(N + O2).

I don’t know if I could do something with a H-bridge. Please help?

Did you have any luck with this? I’m your same situation

I tried with a Arduino controlling a H-bridge, but I have some strange behavior that I couldn’t make much sense of - so I ended up by soldering some relays directly to the original control unit to mimic the button press.

Hi Brian,

I would suggest using 2 Shelly 1s to achieve this since they both have I/O. I have used Shelly 1s successfully for a similar application to what you have.

Let me know if you would like to investigate this route and I can upload photos of my application.

Don’t you need to interlock them?
I found a well working solution with my esp8266, mqtt and 2 relays, but thanks anyway.

Depending on your setup, you may have to make sure they don’t turn on at the same time. I have mine set up where when the first shelly is triggered, it shorts -12v to the wire. When the other is triggered, +12v is shorted to the wire.

Hi daviboi

Can I ask how you wired this? I’m trying to achieve the same thing with 2 shelly’s for a 2 pole recliner motor and want to be sure they can’t operate at the same time.

Hi Triton,

With the application above, I believe that Brian was switching between +24v and -24v on a line with GND always connected. In your application, it sounds like a shelly 2.5 would work. When the relays are off, GND is outputted. When it is on, +24v is outputted to reverse the direction.

Shelly 2.5 wiring diagram

Plus 2PM DC wiring diagram-20240528-134203

Let me know if you have anymore questions.

Thanks for your reply Davi,

I might be confused about how the Shelly 2.5 switches, it looks to me that it requires a 3 wires to the motor, 1 gnd and a wire each for forward reverse. If I’m wrong it might indeed solve the problem but I’ve seen a number of comments in forums suggesting it won’t do it and only double relays will work.

My recliner motor is 2 pole, 29v. So the modules also have to be able to powered by 29v, which limits which Shellys I can consider.

I believe I can achieve it using the dry contacts on 2 Shelly 1 plus modules, which sounds similar to the setup you mentioned you had. I’m interested to know how you wired them to interlock them and prevent both from operating at the same time.

Hi Triton, I apologize for the late reply.

Your motor would be perfect for the shelly 2.5. Hook both poles up to each of the outputs (O1, O2) of the shelly. Then hook 29V+ up to the N terminal and GND to the L terminal(s). When the outputs are off, O1 and O2 will both be shorted to GND (zero potential, no movement). When O1 is triggered, you will have 29V+ on O1 with O2 still shorted to GND giving you potential. You can then stop movement by either turning off O1, or by turning on O2. Either situation would create zero potential across the motor.

Does that make sense? This situation would ensure there is no shorting potential.

I would be happy to provide you photos or videos of this working in action and of the wiring.

Ahh ok, I think I’m getting my head around this.

Any photos or videos you have would definitely be very helpful!