after I added an offset to the temperature of my BME680, I noticed it impacted all the readings of the BME680
in the graphana below you can see that at the moment I implemented the offset, the humidity increased and there is a spike on the CO2 equivalent and the IAQ. Although the last two appear to have reconverged, the humidity is still 20% above
The only way I am aware is to use a sensor filter to alter the output but I’m at a loss as to how to calibrate it accurately and do not know if it should change dynamically across a range of temperature/humidities.
I believe that humidity in the BME680 is dependent on temperature; from memory it is one of the calibration inputs.
I bought a handheld temp and humidity device to calibrate environmental sensors. I have found the biggest element is the position of the sensor in a room; outside/ internal wall, ceiling, cupboard side etc.
I have found that this sensor is wildly inaccurate in relation to another sensor that is placed right next to it (Eve room sensor). I think that the BME680 is just simply not an accurate sensor device and I think I will get rid of it soon unless I find a thread somewhere where I am proven wrong in my opinion.
" Relative humidity (RH) (expressed as a percent) also measures water vapor, but RELATIVE to the temperature of the air. In other words, it is a measure of the actual amount of water vapor in the air compared to the total amount of vapor that can exist in the air at its current temperature ."
Trying to say: device will recalc relative humidity when offset applied.
Here can see 4x sensors data located in same place. First one is Sonoff TH01 Zigbee devices, others names You can see on screenshot - all connected to same ESP32.
Don’t sure this is the same, but I have a DHT11-sensor that has about 2° fault.
I want to offset that, but don’t know how to add an offset to the sensor?
A man with one clock always knows what time it is. A man with two is never really sure.
The BME280 is known for self-heating. I suspect the BME680 is similar. Neither are know to be really accurate, but do generally meet their accuracy spec.
If you want to go down the rabbit hole of more accurate measurements, I suggest starting here to see what is in store for you: