Hi all
I really like to make my garag doors smart in HA.
But im so confused about the wiring part.
First some links
Garage door control – The unofficial Shelly guide!
But im getting diffrent wiring discriptions?
and
I think i want to power the Shelly from 24v DC from Marantec.
But why does the diagram shows 2 wirings to GND?
Chatgpt has helped me (Sorry it messed with the “æ” )
So now i just cant get my head around where the wires should go?
Can somebodu help? 
Thanks!
Have you looked https://paulwieland.github.io/ratgdo/ ?
No idea if it is compatible with your opener. But worth a look.
Hi there
Way to expensive for my taste
Okay getting closer But now im not sure about the IMPULSE.
My collegue that know meny things about wiring has come to this
Normally garage doors gets triggered by short connection of GND and “pulse”
Terminal 2 (impulse) should go to shelly O
GND should go to shelly I (jumper from L)
Nothing to shelly SW
You can test it before (without Shelly) just with piece of wire, connect terminal 1 briefly to terminal2 and door should open/close.
1 = GND
3 = +24V
Door movement is by shorting GND and IMPULSE, so 1-2
And be aware that you are very close to the 50mA limit of your 24V supply.
If you have any hiccups, power it from mains.