Calibration of BME688 sensors

[Keno1]

Hello, I couldn't find any data in BSEC or BME688 documentation about configuration or calibration of BME688. Is calibration required? What does it do to sensors and how do sensor perform without using calibration file? How often do sensor need to be calibrated (once every few day, after device power-up, etc.)?

[BSTRobin]

Hi Keno1,

Once you download latest library(BSEC2.4.0.0)from https://www.bosch-sensortec.com/software-tools/software/bme688-software, you will find calibration part in integration guide. The sensor needs to be powered on and run the BSEC algorithm to calibrate.The time required for calibration depends on the BSEC configuration you are using, as shown in the following figure:

[Keno1]

Hi, sorry, I don't see any picture.. can you reupload?

I assume sensors should be calibrated after each power up? What are the differences between 4-day and 28-day calibration data and what number of days mean? Does calibration data affect all physical sensors, therefore virtual sensors as well? How can I find out whether, after some time after calibration, sensors were fully calibrated?

Kind regards

[BSTRobin]

Hi Keno1,

Whether calibration is required depends on the backend BSEC algorithm. The output of BSEC includes calibration accuracy. If the accuracy is 3, calibration is not required, and usually calibration is required if the accuracy is lower than 3. Calibration does not affect physical sensors, which is relevant to the BSEC algorithm. 28 days means it takes longer than 4 days to complete the calibration.

You can refer to integration guide in BSEC package after you download BSEC2.4.0.0.