Yokogawa Single Channel Oxygen Analyzer System ZR22/ZR402 - Manual (Page 108)

IM 11M12A01-03E 7-16
7.11.1.3 Calibration Gas Concentration Setting
(1) Zero-gas concentration
If zero-gas concentration is selected, the Numeric-data Entry display then appears.
Use this display to enter an oxygen concentration value for the zero-gas calibration;
if the oxygen concentration is 0.98 vol% O
2
, enter 00098.
(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.
• If dehumidification is insufficient, or polluted air is used, a measurement accuracy
may be adversely affected.
7.11.2 Manual Calibration
7.11.2.1 Preliminary
Before performing a 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 pressure plus approx 50 kPa (or measured gas
pressure plus approx. 150 kPa when a check valve is used, maximum pressure rating is
300kPa). This applies even if you are using the ZR40H Auto Calibration Unit.
7.11.2.2 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