Vaisala GMP231 - Manual (Page 43)

Chapter 4 ____________________________________________________ Vaisala Industrial Protocol
VAISALA ________________________________________________________________________ 41
Calibration Commands
NOTE Before calibrating GMP231 using serial line commands, read the
instructions in section Calibration and Adjustment on page 73.
Make sure that the environmental compensation settings of the GMP231
are properly set for your calibration environment; see section Changing
Measurement Settings on page 35.
Adjust CO
2
Measurement
Use the CCO2 command to adjust CO
2
measurement in one or two
points. You can use either a low or high concentration reference
(one-point adjustment), or both (two-point adjustment).
The idea is to let the probe stabilize in the desired CO
2
concentration, and
then input the real CO
2
concentration using the CCO2 command. If you
are performing a two-point correction, repeat for the second point. Then
commit the adjustment by giving the CCO2 –SAVE command. Note that
successfully saving the adjustment clears the calibration date (CDATE)
and calibration text (CTEXT) that have been stored in the probe. Use
those commands to enter a new calibration date and text.
CCO2 [-lo | -hi] [co2]
CCO2 [-save | -cancel]
CCO2 [-reset]
where
-lo = Select low concentration for adjustment. Adjusts
measurement offset.
-hi = Select high concentration for adjustment. Adjusts
measurement gain.
co2 = CO
2
concentration reference in ppm.
-save = Save currently entered adjustments.
-cancel = Cancel currently entered adjustments.
-reset
= Clear user adjustments, set Gain to 1 and offset to 0.