Tradfri motion sensor to control multiple lights, with or without gateway?

Hi,

hope this hasn’t been asked before.

So far I don’t have any Tradfri devices. But I’d like to at a motion sensor and a few lights to my hallway. If possible, I don’t want to add a Tradfri gateway. I have a Hue bridge.

Will it be possible to set up the devices (maybe including them in the Hue bridge) so that the motion sensor turns on the lights, and they will turn off after a few minutes without motion (not sure if that last part would be done via openHAB, the Hue bridge, the motion sensor or if a need the Tradfri gateway…)?

If the bulbs are also Tradfri, you can connect up to 10 directly to the motion sensor, as described here: https://www.ikea.com/gb/en/assembly_instructions/tradfri-wireless-motion-sensor__AA-2140125-1_pub.pdf

However, if you do that I don’t think you can get motion sensor data directly into openHAB…

Any way to get motion sensor data into openHAB to then control the lights with openHAB as well? Will that (only) be possible with the Tradfri gateway?

Tradfri uses the Zigbee protocol, so you will need something to translate Zigbee airwaves to something your device which is running openHAB can understand.

The Tradfri gateway is one method, I guess. I don’t use it.

I have a CC2531 USB dongle with zigbee2mqtt firmware installed. I then run the zigbee2mqtt software and control the Tradfri devices through the openHAB MQTT binding. It looks like zigbee2mqtt supports the motion sensor: https://www.zigbee2mqtt.io/devices/E1525_E1745.html, so this is a cheap option.

OpenHAB has a native Zigbee binding too. You will still need something to translate the Zigbee protocol (such as a CC2531, or other Zigbee USB stick). But you wouldn’t need to run separate software to openHAB. Check the binding docs for more info.

Here’s a search on the forum for the motion sensor.

EDIT: You mentioned the Hue bridge. This is also Zigbee. I have no experience with this, but that may well be all you need to translate Zigbee to openHAB, using the Hue binding.

Some of the tradfri will pair with the hue bridge. The bulbs typically do as I have tried it. Not sure about motion sensor

I’m curious as to wether someone has made this possible myself, as I’m considering different options for a home automation system, and IKEA is pretty convenient.

It says the following on the bindings page for TRÅDFRI:

“The TRÅDFRI controller and sensor devices currently cannot be observed right away because they are communicating directly with the bulbs or lamps without routing their commands through the gateway. This makes it nearly impossible to trigger events for pressed buttons. We only can access some static data like the present status or battery level.”

I suppose this means that in the TRÅDFRI system the controllers and sensors will directly command the devices they control and that they do not announce their events for others to subscribe to. I would think that a simple workaround for that is to somehow emulate and pair a virtual bulb with each sensor or controller device, thus making the controller/sensor send the commands to the virtual bulb which makes them available in openhab.