Campbell EC155, Руководство по эксплуатации продукта

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EC155 CO
2
and H
2
O Closed-Path Gas Analyzer
45
The zero-and-span window of ECMon , span
actual
is reported to the
right of the box where the user enters the span dew-point
temperature. The software calculates span
actual
by taking into
account the dew-point temperature and current ambient
temperature and pressure. The equations used for this calculation
may be found in Appendix B ,
Useful Equations
(p. B-1)
. If drift
(offset or gain) for CO
2
or H
2
O is excessive, it may be time to
replace the desiccant and CO
2
scrubber bottles (see Section 9.5 ,
Replacing the EC155 Desiccant/CO2 Scrubber Bottles
(p. 46)
).
11. With the zero air still flowing and measurements stabilized, click on the
Zero CO
2
and H
2
O button in the Zero/Span window. This will cause the
analyzer to adjust the values of its CO
2
Zero and H
2
O Zero parameters,
forcing the CO
2
and H
2
O concentrations to read zero. Verify the CO
2
and
H
2
O concentrations now read zero.
12. Remove the zero-air source and replace it with the CO
2
span gas. Allow
the gas to flow through the sample cell. Watch for readings to stabilize.
FIGURE 9-10. ECMon Zero/Span window
13. Enter the known concentration of CO
2
(in ppm) in the Span
Concentration box and press Span . This will cause the analyzer to adjust
the value of its CO
2
Span parameter, forcing the measured CO
2
concentration to the value specified. Verify the CO
2
concentration reads
the correct value.
NOTE