Garage Door Electric Eye


Active Member
I remember seeing a topic a while ago where someone was asking about using the existing garage door "electric eye" as an input to a zone on the Elk or for the matter, any automation system. Since the output of the receiver side of the photodetector is NOT a dry contact, this would not work directly. However...

What if you wired in something like the Elk-930 doorbell ( and telephone) ring detector? I don't know how much current the garage door's photodetector draws, but if it exceeds the threshold needed by the 930 would this work? If not, is there another way to do this?



Active Member
The problem is that most garage door systems have current running through the loop that powers the electric eye as well as the light source. The opener monitors for shorts and/or opens in the circuit (like you pressing the internal button) which is how the signaling is done in this loop. Adding other components that alter the circuit might make the whole system fail - immediately or gradually. It certainly voids the warranty. Therefore, it's better to have a separate sensor network for garage doors, and there are tons of articles and posts - even a HowTo - about that here and elsewhere.

Oh, and to pass code in most places, this electric eye needs to operate properly as a safety mechanism. Don't mess with safety.