@tomasandersson Have a look at this thread. I think it contains the answer on your fixed ID (children) question. https://forum.mysensors.org/topic/4834/unique-id-value-ds18b20-temperature-sensors I personally used the sample programs as provided with the MySensors lib with succes the get the DS18B20 onewire working. A resistor 4k7 from +5VDC to the middle pin of the DS18B20 connected to D3 from the arduino and both outer pins of the DS18B20 connected to GND works perfect for me. BR, Boozz

No experience with domoticz, but this may help nevertheless: https://github.com/rejoe2/MySensors-Dallas-Address-ChildID-Consistency You will find some sketches for using more than one DS18B20 on one bus and some explanation also. General remark: as long as you do not change your hardware setup, you should find the same point of measurement reported under a specific temp-Child-ID using the standard sketches. The sketches above go a little further wrt. this.