Shelly 1 Garage Door Automation

I’m looking at connecting my existing Merlin MT100EVO garage door opener to Apple Homekit. I thought it might be a good opportunity to setup a Raspberry Pi with Home Assistant for some future projects too. I’m reasonably comfortable with the Home Assistant setup but had a few questions about the garage door opener.

I found this guide which uses a Shelly 1 wifi relay with a wired contact sensor: although I was planning to use the default Shelly software rather than installing ESPHome like in this implementation:

  1. Does the approach seem reasonable? I’m hoping for a fairly straightforward solution as this is my first project
  2. You stock a contact sensor but it looks like the wire might not be long enough. Which is the correct wire to use if I needed to replace it with a longer wire?
  3. It looks like I need to get doorbell wire to connect the Shelly to the garage door opener. I couldn’t spot it on your website but thought you might use a different name for it? Or just a trip to the hardware store?
  4. Lastly which wire would I use to connect the 30v DC Merlin external accessory power supply to the Shelly?

Shopping list so far

Home Assistant

Garage Door Opener


Hi David,

Yes, this seems like a good way to go about this, especially with the Shellys capability. The MQTT method in that second tutorial would probably be the way I would go about interfacing the two. Personally, I have also been undertaking a similar project, albeit a little less complex. I would just add typically the screw terminals on the back of a garage door are at or below ELV and are safe to work with, however, this may vary between models so I would recommend checking the tech specs and hiring a licenced electrician if you are working with unsafe power sources.

Any old wire to solder onto the end of the sensors should be fine as long as you’re not running it crazy long distances or again high voltages or currents.

Again any wire will do to connect the merlin to the shelly just as I have said before make sure that it is safe to work with. Here is some that would be perfect:


Thanks Mitchell!

I’ll update this post with the end result :grinning_face_with_smiling_eyes:



We’re looking forward to it. Have a Merry Christmas David!


Hi @davidpike, I am about to do this very thing, just waiting for my Shellys to arrive. Was it as easy as you had thought? Any tips? :grinning: Cheers