Yokogawa Single Channel Oxygen Analyzer System ZR22/ZR402 - Manual (Page 114)

IM 11M13A01-02E 7-15
7. Startup
(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 calibra-
tion; 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 hand-held oxygen analyzer to measure the actual oxygen concentration,
and then enter it.
CAUTION
If instrument air is used for the span gas, dehumidify the air down to a dew point of -
20
Њ C 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 valve is fully closed. Open the zero-gas cylinder pressure regulator so that the
secondary pressure equals measured gas plus approx. 50 kPa (or measured 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 Auto 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. In doing so, the Calibration
display as in Figure 7.17 appears.
Enter
Calibration
Manual calibration
F7.17E.EPS
Check the span gas
concentration value
Next
᭜ Cancel calibration
᭜ Change value: 2 1 . 0 0%
Enter
Manual calibration
F7.18E.EPS
Figure 7.17 Calibration Display Figure 7.18 Manual Calibration
(2) Press the [Enter] key to select span-gas 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.