Yokogawa Multi Channel Oxygen Analyzer System ZR22/AV550G - Manual (Page 194)

IM 11M12D01-01E 10-32
10.8.3 Operating the Zero Gas Flow Setting Valve
Operate the zero gas flow setting valve during zero-point calibration in the following
procedures:
(1) When the display shown in Figure 10.35 appears during calibration, open the zero
gas flow setting valve of the flow setting unit and adjust the flowrate to 600 ml/min
±
60 ml/min. To rotate the valve shaft, if the valve has a lock nut loosen the lock nut
and slowly turn it counterclockwise. To check the flowrate, monitor the calibration
gas flow meter.
If the measurement gas pressure is extremely high, adjust the measurement gas
pressure to obtain pressures (listed in Table 10.6)
±
10%.
Table 10.10
Measurement gas pressure (kPa) 50 100 150 200 250
Flowrate (ml/min) 500 430 380 250 320
T10.10E.EPS
Enter
F22E.EPS
Ch1 Manual cal.
Open zero gas valve.
Set flow span gas to
600ml/min.
Valve opened
᭜
Cancel calibration
Figure 10.35 Manual Calibration Display
(2) Adjust the flowrate and select Valve opened from the Manual calibration display.
Check the Trend graph display to see that the measured value is stabilized. Then
press the [Enter] key. The Manual calibration display shown in Figure 10.36 appears.
Close the zero gas flow setting valve to stop the zero gas flow. If the valve has a
lock nut, be sure to tighten the lock nut to prevent the any leakage of the zero gas
into the sensor because the valve may become loose during measurement.
Enter
F26E.EPS
Ch1 Manual cal.
Span calibration
Zero calibration
Span calibration
᭜
End
Close the zero gas valve.
Figure 10.36 Zero-point Calibration Complete (in Manual Calibration)
10.8.4 Operation After Calibration
No special operation of the instrument is needed after calibration. However, it is
recommended that the pressure regulator for the zero gas cylinders be closed because
calibration is not required so often.