1-point adjustment with an MI70-compatible reference probe - GMP231 - MI70

GMP231 User Guide

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User guide
  1. Connect the GMP231 to Port I of the MI70 indicator.
  2. Connect the calibrated reference probe to Port II. Make sure the reference probe is in the same environment as the GMP231’s sensor.
  3. If you are using the calibration adapter to feed a calibration gas to the GMP231, you must feed the same gas to the reference probe also. Refer to the documentation of your reference probe on how to do this, and what accessories you need.
  4. Turn on the MI70 indicator.
  5. Start the adjustment sequence from Main menu > Functions > Adjustments.
  6. MI70 notifies you that automatic power off is disabled during adjustment mode, press OK to acknowledge.
  7. To proceed with the adjustment, select the CO2(I) parameter in the Select Quantity screen. In the Select Quantity screen you can also view the currently used compensation values, and the Last adjustment date information. You can update the date and text using the CDATE and CTEXT commands on the serial line.
  8. You may be prompted to check the environmental settings of the reference probe before proceeding. Press Yes to check the settings and Exit when you have checked and corrected the settings.
  9. The adjustment mode is now active, and you can see the measured CO2 readings and their difference on the screen. Allow the measurement to stabilize. To proceed with the adjustment, press Adjust.
  10. Select To same as CO2(II).
  11. You are prompted if you really want to adjust. Select Yes.
  12. If the adjustment is successful MI70 shows the text Adjustment Done, after which you return to the adjustment mode. At this point you can press Back and Exit to leave the adjustment mode. The adjustment is now completed. If the adjustment cannot be applied MI70 shows the text Cannot adjust, possibly followed by a text stating the reason. A possible reason for an adjustment failure is attempting to apply a very large correction to the reading.