Automatic Calibration

  1. Ensure the Mini-OX is configured for automatic calibration. Refer to Setting the Calibration Type and Measurement Range

  2. Place the sensor probe in the calibration gas, typically fresh air.

  3. Allow the output tostabilize for at least 5 minutes (10 minutes if powering from cold).

  4. Referring to page 9; Apply GND to the CALIBRATE input (pin 3) for a minimum 12s. During the 12s the CYCLE output (pin 4) and the green LED will go high/on, blink rapidly, go high/on, go low/off then return to cycling normally to indicate normal operation has resumed. At this point remove GND from pin 3.

    NOTE:The output will now track to the correct value for the calibration gas.  If calibrating in fresh air, the output value (RS232/Voltage/Current) given equates to 20.7% oxygen with an error of ± 0.2%. After calibration in fresh air the voltage output should read 8.28V. The current output should read 17.25mA, and the RS232 will stream a five character ASCII code representing the O2%.

  5. Calibration is complete.

    NOTE: New calibration values are stored in memory and retained on power loss.