I use the SDS 011 sensor as part of the Sensor.Community network. Setup is identical to Sensor Community, without temperature or humidity meter.
So far everything is going well. For the sake of interest, I took the device with me on the go (via a USB power bank).
At two measuring stations of the Lower Saxony air quality measurement network (Göttinger Straße, Lindener Berg in Hanover), the values on my SDS011 deviated by an average of 40% over several days in December from the officially measured values there. The values I have measured are lower than the officially measured values. The values for PM2.5 differ. The values for PM10 were halfway comparable.
In the meantime, I had ordered another SDS011 for a colleague and then let both sensors run in parallel against the two measuring stations of the Lower Saxony air quality measurement network. Same result, the two SDS011 deviate almost identically from the values of the official station. Again my measurement results are lower.
What could be the problem? I tested the power supply. Operation on the power bank at home does not differ from operation of the SDS011 via a USB cable in the socket.