ESP8266 + SHT30 temp sensor off by ~2.5C

Hardware DIY
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1

I’ve just built a simple temp/humidity sensor with a Lolin D1 mini + SHT30 sensor, using esphome.io firmware, and the temperature reading is above an Aeon ZWave sensor which I think is pretty accurate. I set them 5 cm apart and gathered data for an afternoon, and the difference on average is around 2.5C.

Has anyone experienced something similar with an SHT30 sensor?

If I need to apply a -2.5C offset to the property of the Item, is there an easy way to do that in OH3? Or anyone familiar with esphome.io: is there a way to apply that at the device in esphome.io?

Thanks

2

Use a proxy item. I have not checked code below, but in the lines of.
Also you could use received command if you like that better. You should also check the state so it’s nu null etc.

rule "fixtemperatureoffset"
when 
   Item myesptemperatureitem received update
then
     val tempOffset= 2.5
     myproxyTemperatureItem.postUpdate((triggeringItem.state as DecimalType) - tempOffset) 
end

/S

3

They’re cheap and cheerful. Absolute accuracy not expected, but of course we have no idea what acual reading you get from it, nor how it is massaged by any code before the reported reading.

All sensors packaged with other electronics are prone to self-warming too.

See “offset profile”

4

Hi @rossko57 , I don’t see where to set this in the UI. Do you know if it is only available in the text configs?

5

It’s there, you need to look at the link between channel and Item.

6

Thank you! Found it in Thing definition, Channels, Add Link to Item.