Hello,
Whenever I measure the value of the air quality sensor I get a very fuzzy reading after some initial time, see attached image: 
I read the value every 10s and it varies heavily.
Is this expected/normal or should there be a more stable reading as in the first hour? I.e. is the sensor defect or is there a method to get more “reliable” values?
Best regards,
Mike
In fact, this sensor should be powered for more than 48 hrs before you have a test with it. Or data is useless.
Does this mean that even after a short “power down” the sensor needs about 48hrs before I can extract reliable data?
Or: For how long can I switch off power before I need to wait 48hrs again to get realiable data from the sensor again?
Regards,
Mike
[Update] I put the sensor and the arduino for a day in a location where there are no other electronic devices. It turned out that now the reading is consistent. I.e. I think the other equipment irradiated into the circuit.
I will now shorten the cable between the arduino and the sensor and see if I can at least minimize the influence.
[Update2] I shortened the cable and put a bigger capacitor (10 muF) across the +5V and ground of the sensor. The reading seems to be stable now.
Best regards,
Mike