SmartThings - How to pulse a relay contact
The need to pulse an output on a ZigBee device can be very handy. In my case I needed to simulate a button press on my garage door opener.
I used SONOFF BASICZBR3 that is modified to have dry/no potential relay contact at the output terminal. It is important to do a modification like this before connecting it to a low voltage system like the inputs of a garage door opener.
To make the output pulse when you turn it on you simply create an Automation within SmartThings that turns the device off if itself is turned on. Simple. I have not measured the pulse width but it works each time so I haven't bothered.