Campbell Scientific EC155 CO2 and H2O Closed-Path Gas Analyzer and EC100 Electronics with Optional CSAT3A 3D Sonic Anemometer - Manual (Page 23)

EC155 CO
2
and H
2
O Closed-Path Gas Analyzer
FIGURE 6-4. End views of the analyzer showing the sample intake
(optional heated intake not shown), pump outlet, and zero-and-span
intake
6.2.4.1 Sample Intake
The EC155 can be ordered with a factory-installed intake assembly, or with a
Swagelok fitting to attach a user-supplied intake assembly. If the EC155 is
configured with the intake assembly, it is installed at the factory. No further
assembly is required.
If the EC155 is configured with no intake assembly, it has a 1/8 inch Swagelok
fitting at the front end for connection to the user-supplied intake assembly (see
FIGURE 6-4).
6.2.4.2 Pump
In normal mode the EC155 uses a vacuum pump to pull an air sample through
the sample cell. See the discussion on flow and pressure in the previous
section for pump requirements. The CPEC200 pump module (pn 26399-x) is
designed for use with the EC155. Connect the CPEC200 pump module or
user-supplied sample pump to the 3/8 inch Swagelok fitting at the back end of
the analyzer labeled Pump.
6.2.4.3 Zero and Span
The zero-and-span inlet connects to the pump connection passage near the
outlet of the sample cell. During normal operation the zero-and-span inlet
should be plugged, either with a Swagelok 1/4 inch plug, or with a tube
connecting to a closed valve or manifold system such as the CPEC200 valve
Sample Cell Cable
Analyzer Head Cable
13