YOKOGAWA EXAxt ZR22G, User Manual, Page: 112 / 211

<7. Startup>
7-15
IM 11M12A01-02E
Enter
Span calibration
Close the span gas valve.
Zero calibration

End
Manual calibration
F7.21E.ai
Enter
Check the zero gas
concentration value
Next

Cancel calibration

Change value: 1.00%
Manual calibration
F7.22E.ai
Figure 7.32 Span Calibration Complete Figure 7.33 Zero Gas Concentration
Zero Calibration Check Display
Start Display (in Manual Calibration)
(6) Select “Zero calibration” as in Figure 7.32 to display the zero gas concentration check
display (Manual calibration) . Check that the zero gas oxygen concentration value and the
calibration gas oxygen concentration value agree. Then select “Next” as in Figure 7.33.
(7) Follow the instructions in the display as in Figure 7.34 to turn on the zero gas flow. To do
this, open the zero gas flow valve for the Flow Setting Unit and adjust that valve to obtain a
flow of 600 ± 60 ml/min. The valve should be adjusted by loosening its lock nut and slowly
turning the valve shaft counterclockwise. Use the calibration gas flowmeter to check the
flow.
Enter
Open zero gas valve.
Set flow zero gas to
600ml/min.
Valve opened

Cancel calibration
Manual calibration
F7.23E.ai
Enter
21.00%
0.5min./div
1.00%
21.0%O
2
CAL. TIME
Manual calibration
F7.25E.ai
Figure 7.34 Zero Gas Flow Display Figure 7.35 Zero Gas, Trend Graph
(for Manual calibration)
(8) If “Valve opened” is selected as in Figure 7.34 , an oxygen concentration trend graph (with
the oxygen concentration being measured) appears (see Figure 7.35). The CAL.TIME in
the bottom area of the panel flashes. Observe the trend graph and wait until the measured
value stabilizes in the vicinity of the zero gas concentration on the graph. At this point, no
calibration has been executed yet, so even if the measured value is above or below the zero
gas concentration value, no problem occurs.
(9) After the measured value has stabilized, press the [Enter] key to display the “Zero
calibration complete” display shown in Figure 7.36. At this point, the measured value is
corrected to equal the zero gas concentration setting. Close the zero gas flow valve. The
valve lock nut should be tightened completely so that the zero gas does not leak.
16th Edition : Mar. 19, 2020-00