So I have a sheely 1 mini gen 3 and a 230V legrand chime/doorbell.
Trying to find an equivalent wiring scheme for the Mini - would it be L and N to mains, N from chime to SW and L from chime to O?
Cheers and TIA.
I have a two-wire Golmar Tekna V2 Plus, and with the inspiration from this thread and many others was able to connect it to HA. To help other folks with a similar model, here’s what I did:
Goals
- Notify me when someone is buzzing the building door
- Allow me to trigger the open button remotely
- Don’t interfere with the existing functionality (hardware features should still work)
The Shelly Plus Uni is the star here, as it has a voltometer that allows you to detect the buzzer being pressed, and can be powered through 5V, so I currently have it connected to a USB power pack. In a future iteration I believe we can power it through the 24V bus with an appropriate step-down converter
Wiring
Buzzer
The Tekna has two unused pins marked BUS OUT for connecting another unit or accessory. Normally this operates at 24v, but drops to 18v when the video screen is on (buzzer pressed). We connect these two pins to ANALOG IN & GND in the Shelly. When the buzzer is pressed, voltage drops and the Shelly sends a webhook to HA. The BUS IN pins operate the same way, so I suspect if you have a Golmar model without the BUS OUT you can use those pins instead.
Door Button
Pretty simple conceptually, just connect them to the button contacts on one end and the Shelly OUT 1 on the other. This does require you to disassemble the phone, which only requires a screwdriver and some flat tools for prying. To connect to the buttons I ended up twisting a wire around the contacts and dabbing it with a bit of glue to keep them in place. One of the wires didn’t have a good signal so I put a dab of solder on it as well. Also shrink tubing to keep the exposed parts of the wires from touching, but not necessary if you strip to the exact length in the first place.
Power
As I said, Shelly takes 5VDC so you can just get a USB power cable and connect it to the +5VDC pin on Shelly.
Configuration
Pretty straightforward, a few gotchas/tips:
- Voltage will be “undefined” unless you switch the Voltometer Measurement Range from 0-15 to 0-30
- To prevent the shelly from alerting when wires were disconnected or not powered (0VDC) I created a “Custom Voltage Expression” of
Math.abs(x-18)and alerted on that custom unit instead - To have the button actually operate like a button (On for a half second or so), you have to set it up first in Input/Output settings (Button, Momentary) and then in Automations → Timers (Auto OFF)
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