YOKOGAWA EXAxt ZR22G, User Manual, Page: 144 / 211

<9. Calibration>
9-7
IM 11M12A01-02E 16th Edition : Mar. 19, 2020-00
(2) Select “Calibration setup” from the Maintenance display. Then select “Mode” from the
Calibration setup display (see Figure 9.7).
Now you can select “Manual”, “Semi_Auto”, or “Auto” calibration.
9.2.2 Calibration Procedure
Select both span and zero calibrations or span calibration only or zero calibration only.
Usually select span and zero calibrations.
Select “Points” from the Calibration setup display and then you can select “Both,” “Span” or
“Zero” (see Figure 9.8).
Mode:

Points:

Zero gas conc: 1 . 0 0 %

Span gas conc: 2 1 . 0 0 %

Timing
Enter
Manual
Semi_Auto
Auto
Calibration setup
F9.4E.ai

Mode: Manual
Points:

Zero gas conc: 1 . 0 0 %

Span gas conc: 21 . 0 0 %

Timing
Enter
Both
Span
Zero
Calibration setup
F9.5E.ai
Figure 9.7 Calibration Setup display Figure 9.8 Calibration Setup display
9.2.3 Zero gas Concentration
Set the oxygen concentration for zero-point calibration. Enter the oxygen concentration for the
zero gas in the cylinder used in the following procedures:
Select “Zero gas conc” from the Calibration setup display. The numeric-data entry display then
appears. Enter the desired oxygen concentration for the zero-point calibration. (The zero gas set
ranges from 0.3 to 100 vol%O
2
.)
Enter 00098 for an oxygen concentration of 0.98 vol%O
2
.
9.2.4 Span gas Concentration
Set the oxygen concentration for span calibration. If instrument air is used as the span gas, enter
21% O
2
.
Select “Span gas conc” from the Calibration setup display. Enter the desired span gas oxygen
concentration from the numeric-data entry display.
(The span gas set ranges from 4.5 to 100 vol%O
2
.)
Enter 02100 for an oxygen concentration of 21 vol%O
2
.
Instrument air is here defined as dry air with a dew-point temperature of no higher than -20°C. If
the dew-point temperature is higher than -20°C, use a hand-held oxygen analyzer to measure
the actual oxygen concentration.
When using the ZO21S Standard Gas Unit (for use of the atmospheric air as a span gas), use a
hand-held oxygen analyzer to measure the actual oxygen concentration, and then enter it.
NOTE
• When the instrument air supply is to be used as span gas, cool it to -20°C below dew point
to remove moisture, oil mist and dust from the air.
• If you do not do this to purify the air, then the accuracy of the calibration may be affected.