Konnected Obstruction Sensor data into HA

Konnected Garage Door Opener
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Looking to have some way to get my garage door tripwire / obstruction sensors into Home Assistant.

I have a Guardian 600SL garage door at my home, and a Liftmaster 2.0 garage door at my parents house. I would like to be able to get both of their trip wire info into home assistant. Honestly don’t care if I can operate the garage door via HA, which I know seems like a strange thing to NOT want, but more looking for data as a tripwire more than a actual control the garage door.

I’ve looked at both the Konnected Blaq and White and the ingestion of this data doesn’t seem to be possible on the White? I guess it gets the status of the obstruction from the Chamberlain / Liftmaster in the Blaq, but nothing for the white?

I realize I could buy a second set of lasers and connect them up to an ESP32, and that might be the route I go, but wanted to see what the options are here….

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For the LiftMaster opener this is easy – get the GDO blaQ and it’s built-in. It reads the obstruction sensor state directly from the motor and is plug and play.

For the Guardian opener it’s less easy. The GDO White doesn’t have a built-in way to detect the IR obstruction beam, because it’s not standard on all openers.

One idea that has been batted around is to wire a couple resistors into the IR beam terminals to create a voltage divider, stepping down the voltage on that beam circuit to ~3V something that the GDO White can handle via its INPUT terminals.

If you have a multimeter, try setting it on DC Volts and stick the probes into both terminals of the IR beam wires on the back of the opener motor. Measure the voltage when the beam is intact and broken. It should differ consistently between those two states. Report back and we’ll see if we can make that work.

p.s. I just did that measurement on an old LiftMaster that I have laying around the office. It reads about 6V when intact and 6.5V when the beam is broken.

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I went a different direction with a second set of laser eyes and a Shelly 1 V3. Both can be run off of 12V so hopefully it limits voltage issues…..

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A second set of eyes on a Shelly is a solid way to go, nice work! This thread got me curious though, so today I tried the resistor idea on one of my bench openers (the same old LiftMaster I measured above). It works really well, and all you need is a couple of resistors.

The meter reading was only half the story. The safety beam (obstruction sensor) doesn’t just sit at one voltage. When the beam is intact, the sensor sends a steady stream of short pulses down the wire, about 150 per second. My multimeter was averaging those, which is why it read 6V intact and 6.5V broken. When the beam breaks, the pulses stop. So instead of watching for a tiny change in voltage, the GDO White just counts the pulses.

Two resistors and the INPUT terminals. A 22k and a 15k resistor make a voltage divider that steps the beam circuit down to under 3V, which is safe for the GDO White’s INPUT terminals. I didn’t have a 15k in the drawer, so I used a 10k and a 5.6k in series. The beam wires stay connected to the opener like normal and the divider just taps in alongside them. With the 22k in line, the GDO White can’t interfere with the beam signal, so the opener’s safety reversing works exactly the same as before.

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In Home Assistant you get a regular Obstruction sensor. It turns on within about a quarter second of breaking the beam and clears as soon as the beam is restored. I broke it a couple dozen times on the bench and it caught every one.

It should work on the GDO blaQ too, using Input (1) or (2), but that would be kind of redundant. The blaQ already gets the obstruction state natively from the opener, so for your LiftMaster you’d get it out of the box.

I’ve only tried this on a LiftMaster so far. Other brands may signal differently, so next I’m going to test it on the Genie opener at home. If anyone wants to try it on their own opener, measure the beam voltage first. That resistor combo is only good for a beam circuit up to about 8.7V.

The wiring diagram and the ESPHome config are in the PR if you want the details: GDO White: obstruction beam sensor package; GDOv2-S 1.5.0 by heythisisnate · Pull Request #151 · konnected-io/konnected-esphome · GitHub

After some more testing we’ll release this as an optional feature you can enable on the GDO White. I’d love to hear how it works on other openers!

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Very cool. I might try it on my Guardian 600SL if I can find the time when no cars are in the garage.

What would it take to build this into the white? How did you tie in the resistors? Literally tie them together?