Vaisala GMP252 - 1-Point Adjustment with an MI70-Compatible Reference Probe

When two probes are connected to the MI70 indicator, MI70 uses Roman numerals “I” and
“II” to indicate which port the parameter or function in question is connected to.
8.10.1 1-Point Adjustment with an MI70-Compatible Reference
Probe
1. Connect the GMP252 probe 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 GMP252's sensor.
3. If you are using the calibration adapter to feed a calibration gas to GMP252, you must
feed the same gas to the reference probe as well. 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 o 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 CO
2
readings and
their
dierence on the screen. Allow the measurement to stabilize. To proceed with the
adjustment, press Adjust.
GMP252 User Guide M211897EN-D
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