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GrainPro
®
Carbon Dioxide Analyzer Instruction Manual
MA4068RAD0718 - 2
5.7.1
Calibration
a)
Zero Calibration shall be done using ambient
condition (CO
2
concentration at ambient is about
0.03% to 0.04%) or by using pure Nitrogen.
b)
Span Calibration shall be done using 50% CO
2
concentration. See section 5.7.2 Calibration
process, h.
NOTE:
If 50% CO
2
is unavailable, use only Zero calibration.
See section 5.7.2 Calibration Process (g).
5.7.2
Calibration Process
a)
In the Main Menu page, press Down Key to
enter the Calibration mode.
b)
Enter the Password (321) and expose to
ambient air or connect to pure nitrogen.
c)
Press Enter Key
to confirm, then the CO
2
Analyzer is ready for Zero calibration.
d)
The “Apply Zero Gas” prompt will be displayed,
and the CO
2
Analyzer will take samples for 30
seconds (displayed on the screen).
e)
CO
2
Analyzer will be set to zero, only if count
value is in between 50 to 999, ideally 500.
f)
After taking the samples, “Zero Cal Done”
prompt will appear otherwise
“Zero Cal Fail”
prompt will be displayed.
NOTE:
In case of Zero Cal Fail, refer to the
TROUBLESHOOTING GUIDE (8) >Zero Calibration
(8.1).
g)
After Zero calibration, “Span Gas” will be
displayed. To discontinue the Span Calibration,
press “SET” Key
to exit. However, enter gas
concentration values for which instrument is to
be calibrated (Ideally 50) to continue the Span
Calibration.
h)
Connect the CO
2
Analyzer to 50% CO
2
bag/tank
using
available calibrated
instrument
as
reference.
i)
Press Enter Key
to start and the “Apply Span
Gas” prompt will appear. CO
2
Analyzer will take
samples of target gas for 120 seconds
(displayed on the screen).
