Grove Oxygen Sensor Pro (Pre-calibration) always reads 25% O2

Products & Technology Grove
3

Hi Citric, thank you for the extra steps to try.

  1. The developer documentation you provided is for the ME2-O2, not the GCC2330 O2 Sensor Pro. The Pro sensor has both UART and analog outputs, so I expect the UART communication to not also require the analog output from the sensor.

    When I try the sensor with an Arduino Uno (connecting GND to GND, VCC to 3.3V, and V0 to A5, then uploading the code from your link) I see:

    Vout =1.96 V, Concentration of O2 is 20.59

    Which is close enough to ambient O2 concentration. But again, this value does not change (beyond ~0.04%) even after preheating for over an hour and enclosing it in an environment with low oxygen. I also repeated the test with VCC=5V, which is actually the specified operating voltage per the datasheet.

  2. Thank you for the clarification - I’ve been waiting for double this period, so the sensor should be warmed up when I go to test it.

  3. I reverted the baud rate in my original program to 9600, but the result is still the same when measured via UART (“O2: 25.00 %”).