Chamberlain Group elected to hide my solution by sneakily setting my post to private on their community. Here's what they blocked.
NOTE: Welcome fellow Chamberlain victim! This write up isn't intended as a complete build guide. I just wanted to chronicle some of what I did to come up with a solution. That said, as long as you have some basic skills and/or a desire to experiment, you will be successful.
I earlier had posted about how I integrated an Alexa controlled, inexpensive single channel relay so I could open and close my 8550 from Alexa, as well as via IFTTT geofencing when I entered the neighborhood.
This worked well, but I didn't like how if the door was already open, the door could close with another open command since the trigger is stateless (dumb). For example: your family is home and they've got the door open. You roll into the 'hood and IFTTT triggers the door as it should, but because it was open it now closes.
I realized there was an easy and still inexpensive solution to this by using a two channel relay in conjunction with a magnetic window switch that has both NO and NC contacts. By mounting the magnetic switch to the door, and wiring each relay channel onto one of the contacts of the switch, you create a physical "toggle" such that when the door is open, the circuit is broken and further open commands won't work.
Likewise if the door is closed, subsequent close commands won't do anything.
Alexa/Google/IFTTT still are clueless about the state of the door, but now they just shoot blanks when a trigger is given and the reed switch has the circuit open.
This "upgrade" brought the total price up about $12 from my previous setup: an extra $6 for the two channel relay over the one channel, and $6 for the magnetic reed switch.
LiftMaster 883LM Security+ 2.0 MyQ Door Control Push Button $11.95The rest of the materials are again things I had laying around already:
MHCOZY WiFi Wireless Smart Switch 2 channel Relay Module (Amazon) $19.90
Magnetic Switch with NC and NO contacts $5.84
- a different power supply. This relay needs 7-32V AC or DC, so a 5V USB wasn't sufficient. I found a 12V DC wall wart in the junk drawer that was pressed into service
- A three wire PC power cord to run from the reed switch back to the relay. One wire each for COM, NO and NC
- wire ring terminals - not needed but I felt they'd hold better to the switch terminals if there was any vibration vs bare wire loops
- some pieces of metal and wood, screws, wire nuts etc
After installation, and reprogramming all my Alexa routines such that the various "open" commands used Channel 1, and all the "close" commands used Channel 2, it all works like a charm!
When the door is closed, and the magnet is away from the reed switch, the NO terminal is closed. This is wired to channel 1 for OPEN commands. When the door is fully open and the magnet engages the switch, the NO terminal opens, disabling the OPEN command circuit, and the NC side closes. NC is wired into Channel 2 for CLOSE commands. Sounds confusing I know. Really though, how you wire it up doesn't matter. If you get it backwards you just use the channels the other way around when you program Alexa etc. Matters not. The point is now the correct channel can trigger the door at a given time without the other channel interfering.
This way of doing it will work for any garage door. If yours doesn't have Security+2.0 then you don't need the 833LM push button and things are even cheaper and easier.
Note: if you have a MyQ, while this solution itself can't show you the open/close state of the door, the MyQ app will.
Here's all the stuff. Thanks to user Ryan Frye for the shot of wiring into the micro switch, which I neglected to get previously:
L-R, starting at the top (full size photo here):
- Voltmeter just to make my life easier figuring out what was NO and what was NC, white 2 channel inching relay and 12V power supply, the black reed switch halves, a couple pieces of metal to mount the magnet half to my garage door, the ring terminals and PC power cord
- Magnetic reed switch
- 833LM from previous installation, showing how to tap into the microswitch
- reed switch mountings. Terminal side mounted to some wood of appropriate length and attached to the ceiling joist. PC cord runs off to the 2 channel relay.
- 2 Channel Relay mounted next to 833LM
- Entire assembly hidden up in ceiling joists above my 8550
So if you're handy, for a one time $40-$50 (and a couple hours of your time) you can get the smart home integration Chamberlain is so stubbornly resisting.
I have since ditched the magnetic portion of the reed switch that was mounted to the metal brackets in favor of a 3" rare earth magnet bar.
With the occasional variation in stopping location of the door, sometimes the reed switch magnet wasn't lining up properly. The longer rare earth magnet, plus its inherent strength, did away with this problem.
if you go the rare earth magnet route, get yourself the kind with screw holes built in. These magnets are so strong that they were tending to align themselves over time to an area of the door that must have had more steel in it. I Gorilla Glued mine down eventually to keep it in place.