EN
LoRaWAN COMFORT CO2 - Guide utilisateur / User guide version V1.1.1
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2.4. Maintenance and calibration of the CO2 sensor
2.4.1 Maintenance of the device
The LoRaWAN COMFORT CO2 device does not require any maintenance if the following criteria are respected:
Automatic calibration activated in a regularly ventilated zone.
OR
Manual calibration is performed every 6 months at “fresh air” being 400 ppm (could be outside protected from wind and sun or in a room that
has been ventilated almost 20 consecutive minutes).
To indicate that the calibration is performing the LEDS present on the casing are running as described below.
Calibration is running :
The 3 LEDs are blinking one
after the other every 5 seconds
during around 10 minutes
Calibration done :
The 3 LEDs are blinking
one after the other every
seconds 5 times.
2.4.2 Automatic calibration
IMPORTANT: By default, the automatic calibration is activated and runs continuously with a period of 8 days. There is no
need of a user intervention.
This period by default, 8 days period, as to catch low-occupancy and other lower-emission time periods and favorable outdoor wind-directions
and similar which can plausibly and routinely expose the sensor to the truest fresh air environment.
In each new measurement period, the sensor will compare it to the stored one, and if new values show a lower CO2-equivalent raw signal while
also in a stable environment, the reference is updated with these new values.
If needed, this period can be extended to 2 weeks or 1 month by configuration (register S356).
The algorithm also has a limit on how much it is allowed to change the baseline correction offset with, per each cycle, meaning that self-cali-
brating to adjust to bigger drifts or signal changes may take more than one cycle.
Example of a meeting room:
IMPORTANT: If such an environment can never be expected to occur, either by sensor locality or ever-presence of CO2 emis-
sion sources (24h/24h building occupancy for example), or exposure to even lower concentrations than the natural fresh air
baseline, then automatic recalibration can’t be used. In this case, the manual calibration must be used.
NOTE: The automatic calibration is deactivated if a blackout period is activated (S324).
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