Yokogawa Single Channel Oxygen Analyzer System ZR22/ZR402 - Manual (Page 110)

IM 11M12A01-03E 7-18
(7) Follow the instructions in the display as in Figure 7.23 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.EPS
Figure 7.23 Zero-gas Flow Display
(for Manual calibration)
(8) If “Valve opened” is selected as in Figure 7.23, an oxygen-concentration trend graph
(with the oxygen concentration being measured) appears (see Figure 7.25). 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.
Enter
21.00%
0.5min./div
1.00%
21.0%O2 CAL. TIME
Manual calibration
F7.25E.EPS
Figure 7.25 Manual Calibration, Trend Graph