Tradfri bulbs with different colour temperature ranges


I’ve got loads of Tradfri bulbs round the house. I’ve been messing with 2 in the kitchen and had to re-pair them both.

They’re running the same FW and using the same DH.

One has a colour temp range from 2200 to 4000 in the app. The other has a range of 2700 to 6500 in the app.

Any ideas? Ideally, I want them both to go down to 2200.


It might be implied, but are they the same model bulb? Any differences of detail when you look at them in the IDE?

I see that the DTH overrides the ‘vid’ of a number of Tradfri bulbs in the fingerprint, which suggests one of the two (the 2700 to 6500 one) is either unknown to the DTH or is not being recognised correctly for some reason.

Something you could do that might be pointless, but is also harmless, is to edit the offending bulb in the IDE, change the name of it, and update it (and you can then do the same to change it back to how you had it in the first place). In my experience that makes sure that the metadata in the device handler is up to date.

I bought them at the same time and before I messed around with them they both did the same and the lowest setting was 2200. I then re-paired both one after the other so it’s not like there might have been an update to ST or anything. I might try removing them again and adding them through the classic app.

Weirdly, if I use Alexa, I can set the colour of the one that only goes 2700 to warm white. When I check ST, the value shows 2200 but there is no ‘blob’ on the slider. If I then touch the slider at the lowest point it sets it to 2700 again. For the moment, I’m just leaving it alone after setting it in Alexa as we don’t change them.

Try to delete them, and add them again. Make sure you don’t have any custom DH written for these bulbs in your IDE.
You might have got some wrong DH assignment and that has messed up things.

In theory, when you delete them, and after re-add them, then they should start with a clear slate. (No, previous information stored.) They should have both the right stock DH assigned. And the display should be the same for both.

I think that’s what I just did. I’m messing around with a Pi and Home Assistant at the moment to try and get everything running locally. I removed these 2 bulbs from ST, added them to Home Assistant and then added them back to ST. Both are using the same DH in ST - “ZLL White Color Temperature Bulb 5000K”. Both have the same FW version - 0x12217572. Both behaved the same way before I removed them and added them again. Both were added back into ST within 30 seconds of each other.

They’re both allowing me to set the colour temp to 2200 in Alexa at the moment so I’m probably going to leave them alone.

What you are saying regarding Alexa, is not a surprise.
The app displays a setting defined in the DH for colour temperature range. But I believe the DH is not really limiting what temperature request is sent to the bulb. So Alexa doesn’t depend on the DH’s visual settings, so it can change the color without conflicting it.

Indeed it will set any colour temperature:

def setColorTemperature(value) {
	value = value as Integer
	def tempInMired = Math.round(1000000 / value)
	def finalHex = zigbee.swapEndianHex(zigbee.convertToHexString(tempInMired, 4))