07-17-2019 07:32 PM - edited 07-17-2019 07:35 PM
Hello, can u help me with some problem. Sensor measures valid data only after power on (two/three times) and then the temperature start go up and humidity go down from real values, after some time temperature/humidity stops go up/down and shows incorrect values. For example, measured temperature 40 °С, but real is 25 °С, and measured humidity is 16 %, real value is 40 %. Measurement period 3 seconds, pressure measurement is always correct, gas measurement not used. I am using BME sensor API version 3.5.9 and all recommended initialization and measurement procedures, I2C interface. Why my temperature/humidity measurements become wrong with time?
07-19-2019 11:41 AM
Hi heavyC1oud,
Typically, while heating the gas sensor, depending on how the heater element is duty cycled, the internal temperature of the device increases. Additionally, if you have other heat sources on the PCB like a power management unit or a processor, this could lead to additional temperature increase that is measured at the sensor. This temperature increase also causes the measured relative humidity to drop by a relative amount. The BSEC library, can compensate for the heat generated by the sensor itself, and you can additionally input the expected temperature increase due to other heat sources and the BSEC library will give you the corrected temperature and humidity.
07-31-2019 01:29 PM
Hi kgoveas,
i got the same problem like heavyC1oud but I use the BME280. Can I use the BSEC library for the BME280 as well to get rid of the temperature offset? Do you know if there is any chance to download the source code from the BSEC library?
08-01-2019 10:26 AM