What do I need to do to trigger a Shelly RGBW2 external switch from a Infrared door sensor

Hey guys,

I’m working on a simple smart home project where I’ve installed some 24V LED COB strips inside a pantry cabinet.

I’m using an infrared door control sensor to detect when the door opens and closes and turn of the LED strip accordingly.

I also have a Tuya Smart Home dimmer connected to control the lighting and dim the LED strip at night.
The 24V power supply is connected to the smart dimmer, the door sensor, and the LED strips.


While this was all working, I wasn’t too happy with the dimming performance of the Tuya dimmer so I’ve decided to use a Shelly RGBW2 dimmer instead which provides much better low dimming performance (via PWM). Unfortunately, the door sensor doesn’t play nicely with the Shelly device and causes the lights to flicker at low dim levels. I think this might be due to the sensor having some additional electronics which also dims the lights to off when the door closes.

Instead of wiring the door sensor inline, I’m thinking of using it as a switch to control the Shelly. This however doesn’t appear to work as the output from the sensor still provides a current instead of a hard 0 when the door is closed.


I need to convert the high/low output to a more discrete output. Briding the shelly with a simple push button switch obviously works. I’d rather not use a relay to keep things quiet. Do I need some resisters, transistors, MOSFETs, Optocoupler, or something else? Alternatively, if anyone has any suggestions on stopping the flickering, then maybe that might be simpler.

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How did you get on it the end?

I think hardwiring wardrobe sensors to the Shelly should be able to produce an optimal result… but I am still researching

Not sure what the author did but easiest would be obviously to just wire a “input” sensor (like infrared/pir/etc.) to the dedicated input pin and configure it accordingly (like when the input goes high to turn on the lights for x seconds/minutes despite the signal going off again).

In case the stock shelly FW can’t do/allow this quickest path is probably to charge esphome on it :rocket: