Hi folks,
my setup shows me a behaviour I did not expect 
So I hope someone can point me to the right direction. That’s what I did:
I configured my Netatmo Healthy Home Coach to write it’s data to a MQTT broker. So I get entries on this side like these:
mytopic/NHC_CO2 1240
mytopic/NHC_SignalStrength 3
On HA-Side, I created mqtt sensors:
- platform: mqtt
name: "Netatmo CO2"
unit_of_measurement: "ppm"
icon: mdi:periodic-table-co2
state_topic: "mytopic/NHC_CO2"
- platform: mqtt
name: "Netatmo Signalstärke"
icon: mdi:signal
state_topic: "mytopic/NHC_SignalStrength"
Fine; when MQTT receives updates, my sensors get updated accordingly.
Every entity state should go into my InfluxDB for visualizing with Grafana. So I’m using this not too fancy code in configuration.yaml to achieve this:
influxdb:
host: '10.8.0.1'
port: '8086'
database: 'mydb'
username: 'myuser'
password: 'mypassword'
max_retries: 3
default_measurement: state
Now my problem: as soon I define unit_of_measurement in my sensor’s config, this will be the measurement name used in InfluxDB. Means: I expected the CO2 values under sensor.netatmo_co2, but in fact they’re stored under the name ppm. But for sensor.netatmo_signalstarke everything is fine: it has no unit_of_measurement defined.
Same for temperature. Which means: all values with unit_of_measurement defined as °C go to InfluxDB measurement °C which means one weired graph with all temperatures from all rooms in it.
That’s not what I expected, and that’s not what I need. So my question is: what do I miss?
Using HA 0.88.1 (Hassbian on RPi 3); InfluxDB 1.7.4-1(on external server machine); mosquitto-1.5.6 (on external server machine) and appreciate every single hint 
Cheers,
Marianne