Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 103)

<7. Startup>
7-15
IM 11M12A01-02E
(2) Span gas concentration
With “Span gas conc” selected in the Calibration setup display, display the Numeric - data
Entry display and enter an oxygen concentration value for the span gas calibration; If
instrument air is used, enter 02100 for a 21 vol%O
2
value. When using the ZO21S Standard
Gas Unit (for use of the atmospheric air as a span gas), use a portable oxygen analyzer to
measure the actual oxygen concentration, and then enter it.
NOTE
If instrument air is used for the span gas, dehumidify the air by cooling to a dew point of - 20 ºC
and remove any oil mist or dust.
7.12.2 Manual Calibration
7.12.2.1 Preliminary
Before performing manual calibration, be sure that the ZA8F Flow Setting Unit zero gas flow
setting valve is fully closed. Open the zero gas cylinder pressure reducing valve so that the
secondary pressure equals sample gas plus approx. 50 kPa (or sample gas pressure plus
approx. 150 kPa when a check valve is used, maximum pressure rating is 300 kPa).
This applies even if you are using the ZR40H Automatic Calibration Unit.
7.12.2.2 Calibration Procedures
This manual assumes that the instrument air is the same as the reference gas used for the span
gas. Follow the steps below to conduct manual calibration:
(1) Press the [Setup] key in the Basic panel display to display the Execution/Setup display.
Then select “Calibration” in the Execution/Setup display.
Enter
Calibration
Manual calibration
F7.17E.ai
Check the span gas
concentration value
Next

Cancel calibration
 Change value: 21.00%
Enter
Manual calibration
F7.18E.ai
Figure 7.17 Calibration Display Figure 7.18 Manual Calibration
(2) Press the [Enter] key to select “Span calibration”. The Manual calibration display shown
in Figure 7.18 then appears. Check that the oxygen concentration for the span gas in this
display coincides with the oxygen concentration in the calibration gas actually used. If the
check results are assumed to be OK, select “Next” in the Manual calibration display.
8th Edition : Jan.13,2012-00