Liftmaster LM80EVF Close function


I don’t have a Garadget system yet. I have been looking for a way to integrate a Liftmaster LM80 operator with a Shelly device, for remote opening and closing via smartphones. I need to use Shelly as there are users who are just about comfortable with the Shelly app, but are very reluctant to use something else!

My question is, is there a dedicated close function? To allow a remote user to issue a close command, without needing to know whether or not the door is open. As far as I can tell, all the remotes just offer one button, which opens the door if it’s closed, and vice versa. I need to be able to close a contact, which does nothing if the door is already closed, and closes it if open.

I hope this makes sense. Thank you for reading this far.

Separate open/stop/close buttons can be found on the industrial openers. Consumer models typically have only one button for all functions.

You can route the connection to the remote close contacts in series via the normally closed switch installed at the closed position of the door. This way when the door is fully closed the switch will open disabling the remote control.

Thank you so much for that. I didn’t know that domestic operators didn’t generally have separate functions.

What’s frustrating is that the Liftmaster MyQ smartphone app (which I prefer to not use for various reasons) does offer the ability to open, or close, independently. And a few other useful features. But, this uses their (ridiculous?!) Security+ 2.0 encrypted comms protocol, which I understand they fairly aggressively protect against reverse engineering.

I will investigate the possibility of incorporating the sensor switches. There is a separate contact for the intruder alarm, that closes when the door is closed. Maybe I can implement some logic to do what I need. The issue is that I can’t disable the remote when the door is closed, as I occasionally also want to open it remotely (to enable people to get in there when nobody is home to open the door).

Thank you again. I really appreciate your taking the trouble to reply.