Control Liftmaster LA400 Gate Opener via HA?

There is a lot of discussion in a few different garage door opener threads, but I can’t find a gate opener specific thread, so I am posting this

I have a Liftmaster garage door opener with MyQ, and the LA400 gate connects to the garage door opener so in the app I see both. As we all know, the API sucks and for me currently just flat out stopped working. When it worked, it was okay as it let me control the door and gate, but it was slow and required the internet.

The go-to fix has been the HomeKit add-on, which lets you control the door and gate locally, but they have now nuked that device and support for it is/has ended

There are many solutions for garage doors such as OpenGarage and Ratgdo, but so far none of them support the LA400 gate openers that I can tell.

Has anyone hacked something together to get an LA400 gate opener to work? I know @PaulWieland commented that they may be supported by Ratdgo in the future, but I’m not sure when that is. Will the hardware be the same?

Would love to know what y’all’s solutions are for gates, specifically the LA400

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I have tried a little of everything

RasPI gpio triggering relays
Wifi relay
Zwave zooz 16

What i would really like is a simple POE relay. All technologies worked well. The difficulty for me is determining what hardware i want at gate.

L400 has an Open and Single Button Control(SBC). You really only need to get a relay to close those contacts.

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What did you use to determine if the gate was open or closed?

when I used RasPi i used magnetic door contact to GPIO. There is heavy duty version used for garage that are great.

I use Zen16 now. I does not have contact but zen17 version does. I have my dahua doorbell that I still need to install. It has relay for gate open and input for open/close sensor. I may switch to that.

does your look like this? the SBC terminals would need to be wired to one of the solutions being discussed

Yep, pretty much identical

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I have two RSL12UL Liftmaster Gate motors that I would love to onboard onto Home assistant.

I ordered a ratdgo 2.5 to try it out. I can’t find it now, but there was a chart with a list of remote openers that were compatible and the 1-button opener I use was on the list, so here’s hoping myself or the guy that services the gates can figure it out!

If not, I may set up a third remote opener and build a wireless Lego button presser.

I found waveshare poe modbus 8ch relay

I may use this since it look simple and easy to power. I may use same for my sprinkliers. They have wifi version and other type product.

Dont do waveshare
Infont think modbus is to spec so not easily added to HA. I got a similar IP based relay using standard get calls instead.

Interesting thread

I just ordered the expansion module K1D8080-1CC

I would wait to learn more details before ordering, but with the amount of comments around here from people with LA400’s, I have a feeling they may end up being out of stock!

Another option

If you have the expansion board, you can interface directly to the OPEN and CLOSE contact closures, plus the two AUX relays to get open and closed status. I did this quickly with two Shelly 1s I had laying around, using one for open and one for close. I tried a Shelly 2.5, but the output has 24VDC on it, so it shorts out the Shelly when you connect COM and OPEN or CLOSE. I pulled power from the always-on accessory power on the main board.

My config is below, including functionality to only hold the relay for two seconds when you send the open or close command. The only thing I have not yet configured is a way to interpret the flashing AUX1 output when the gate is in motion.

        - name: "Driveway Gate Open Relay"
          payload_on: "on"
          payload_off: "off"
          qos: 2
          state_topic: shellies/shelly-drivewaygate-open/relay/0
          command_topic: shellies/shelly-drivewaygate-open/relay/0/command
          json_attributes_topic: shellies/shelly-drivewaygate-open/info
        - name: "Driveway Gate Close Relay"
          payload_on: "on"
          payload_off: "off"
          qos: 2
          state_topic: shellies/shelly-drivewaygate-close/relay/0
          command_topic: shellies/shelly-drivewaygate-close/relay/0/command
          json_attributes_topic: shellies/shelly-drivewaygate-close/info
        - name: "Driveway Gate Open Status"
          expire_after: 600
          qos: 2
          payload_on: 1
          payload_off: 0
          state_topic: shellies/shelly-drivewaygate-open/input/0
        - name: "Driveway Gate Closed Status"
          expire_after: 600
          qos: 2
          payload_on: 1
          payload_off: 0
          state_topic: shellies/shelly-drivewaygate-close/input/0

  - platform: template
        device_class: gate
        friendly_name: "Driveway Gate"
        unique_id: 53a1703a-bab0-44ea-8747-144b7b0f370f
        value_template: "{% if is_state('binary_sensor.driveway_gate_closed_status', 'on') %}closed{% elif is_state('binary_sensor.driveway_gate_open_status', 'on') %}open{% endif %}"
          - service: switch.turn_on
              entity_id: switch.driveway_gate_open_relay
          - delay: 2
          - service: switch.turn_off
              entity_id: switch.driveway_gate_open_relay          
          - service: switch.turn_on
              entity_id: switch.driveway_gate_close_relay
          - delay: 2
          - service: switch.turn_off
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Thanks for posting!

Question for you as I’m not a big yaml expert. Does this make a single button to open and close the gate, similar to a garage door opener?


The first half of the yaml creates two switches (open and close) and two sensors (open and closed), and those individual components are combined in the second half to make the gate cover object. In your dashboards, you’d just add the gate object and control it like any other cover.

If you only want a simple button that toggles the gate like a garage door remote, then you could just interface to the SBC connection on the main LA400 board.

Reading this thread, the RATGDO github issues thread and the above reddit thread and trying to gauge the status of using RATGDO with Liftmaster LA400 (the Gate).

Most of the threads predate the 2.5 TATGDO with Security 1.0 which might help in getting the RATGDO to work with the Gate

If look at the control panel on the Liftmaster LA400 I see the SBC connector which is used by iSmartgate whcih would be the connection for the red and black wire… BUT where to place the white wire?

If I ordere the expansion board, I would ask the same question.

Any ideas?**

someone who’s tried can confirm, but the way I understand, if using the SBC controller - seems like from various posts, you’d have to use the dry contact interface on the right side of the RATGDO - so it would only be 2 wires?

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I just received a 2.5 ratgdo and am trying to figure out how to wire it up to the LA400 now. Has anyone figured this out yet?

I have been looking into this.

I bought a RATGDO 2.5 and was disappointed to open my gate motor and see the contacts weren’t easily laid out. I have been digging. As stated above, the SBC seems to be the golden ticket for dry contacts.

(taken from manual)

The Expansion Board is seemingly the easiest option to get access to limiters for Open and Close but at $150 it’s not really my first choice. Model: LiftMaster Expansion Board (UL325)

The black box in the bottom right hand corner is what I think would be the easiest access to what you’d need for a dry contact RATGDO.

But this isn’t too feasible due to cost.

I want to dig into what the color wires on the arm do.

Now, I haven’t tested this yet but I stumbled across this video ( where a guy is repairing his LA400 opener and it gives a pretty good view of the limit switches on the inside of the arm. It looks like the Brown and White Wires are Limit switches and the Yellow might be the common line. In the next few days when I get a chance I am going to take a multimeter and see what the terminals on the gate board say at different positions.

I’m hoping we can get a reading out of these colored wires going to the operator.

My 3rd RATGDO is still on it’s way and I’m not willing to rip my other 2 out of the other doors to test this. If anyone makes progress, please update me!

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great find! are you thinking using the voltage differences the guy shows in those videos, the ratgdo ‘may’ be able to decipher whether the gate is open/close/moving? fingers crossed on this solution

Correct. I believe a RATGDO in dry contact mode would be able to use the voltage sensed as the fully open and fully closed limit switch. Voltage readings today look promising but I am waiting on my RATGDO to be delivered in approx 3 weeks.

Yellow and Brown Measurements
Gate Closed

Gate Opened

Yellow and White Measurements
Gate Closed

Gate Open

So they -seem- to read properly at the open and close but I’ll admit two things:

  1. I didn’t expect a negative reading for White measurement. Not sure what to make of that.
  2. The voltage measurements were not a static number while the gate opened and closed. The White and Yellow got to -5.72 while the gate was opening before settling on -1.41 at full open.

I feel like the RATGDO might be able to read despite this but I’ll need to compare to my other gate that is using dry contacts.

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So, if the expansion board uses 4 wires and has all that io, pretty obvious it’s some kind of communications bus, then if you could decipher that bus wouldn’t it give you all the info you needed and then some? You really just need to figure out where ground is, then look for your signal. I’d imagine based off the graphic you posted you have ground, power, TX and RX. Is it as simple as black ground, red power, then yellow and blue are your rx tx?