Campbell Scientific EC150 CO2 and H2O Open-Path Gas Analyzer and EC100 Electronics with Optional CSAT3A 3D Sonic Anemometer User Manual
Page 35
EC150 CO
2
/H
2
O Open-Path Gas Analyzer
5. Disconnect the EC150 temperature probe from the EC100 and connect the
shroud temperature probe in its place.
6. Connect the EC100 to a PC with the EC100 USB cable (pn 26563).
7. Resume power to the EC100/EC150.
8. Wait for all the
Gas and Power LED status lights on the EC100 panel to
turn green.
9. Launch ECMon, select the appropriate USB port, and click
Connect. The
main screen should now be reporting real-time CO
2
and H
2
O
concentrations.
10. Click
Zero/Span. A graph will appear in the lower half of the zero-and-
span window showing measured CO
2
and H
2
O concentrations (see
11. Connect a gas cylinder of known CO
2
concentration to a pressure
regulator, then to a flow controller, and finally to the intake of the shroud.
Optimally, the concentration of span CO
2
should be near the concentration
of CO
2
being measured in the field.
12. Beginning with both the pressure regulator and flow controller turned off,
use the pressure regulator to slowly increase pressure to the recommended
setting for the flow controller.
13. Set the flow between 0.2 and 0.4 LPM.
14. Monitor the ECMon zero-and-span graph and wait for the CO
2
measurement readings to stabilize (5 to 10 minutes). Once stable, record
the reported CO
2
concentration.
Use a mixture of CO
2
in air (not nitrogen) for the CO
2
span gas.
The use of pure nitrogen as the carrier gas will lead to errors
because the pressure-broadening of the CO
2
absorption lines is
different for oxygen and nitrogen.
NOTE
25