01-03-2023 05:30 PM
I did my first measurements with the BME 688 Dev-Kit and noticed that the measured temperature is quite high. Instead of getting around 22°C (room temperature) the sensors measured between 42-45°C.
I can imagine it is because of the heating gas sensors. Unfortunatelly there is no heater profile with room temperatures. Is it possible to customize the heating profiles or may turn it off completely?
01-03-2023 09:42 PM - edited 01-03-2023 09:50 PM
That's correct. What is purpose for BME688? Do you want to use gas scanning feature in BME688?
If yes, BME688 is not appropriate for room temperature due to heating profile.
01-04-2023 08:22 AM
first of all, thank you for your quick response.
Currently we use an extra sensor to measure temperature and humidity. Would have been nice if we could also use that data to get rid of the other sensors. Additionally that seems to influence the humidity measurement. Towards your statement, for which temperature areas can I trust the measured temperature? Is there any approximation?
Yes, our main purpose is to use the gas sensor in future but I was wondering if the sensor is working correctly or something is incorrect.
Another short question, the Andriot app seems to be a demo version. Is the full version not released yet? Or do I can get it from somewhere else?
01-18-2023 12:38 AM
As long as you are using gas scanning mode, we don't recommend to use temp and humidity as you understand.
In terms of Android app, I don't think we are going to release whole source code, but only app level.
We might upgrade official version, but not plan it right now.
02-05-2023 10:09 PM - edited 02-05-2023 10:12 PM
Perhaps we have to differentiate between collecting a lot of gas probes for training the AI model vs. using the BME688 in the field to take a single measure. You may have a look at https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bme688-ds000.pdf, p. 18, fig. 2. You'll see different types of modes a forced mode, and a parallel mode. The forced mode seems to be the right for you. First temperature, humidity and pressure is messured, just after that pre-heating and heating for gas measurement is startet and gas measurement is done. in the sleep phase after the measurement the sensor has time to cool down and is "cold" before the next round starts again with unbiased temperature measurement.