Campbell Scientific CPEC200 Closed-Path Eddy-Covariance System - Manual (Page 23)

CPEC200 Closed-Path Eddy-Covariance System
4.2 Theory of Operation
The CPEC200 is used for long-term monitoring of atmosphere–biosphere
exchanges of carbon dioxide, water vapor, heat, and momentum. This
complete, turn-key system includes a closed-path gas analyzer (EC155), a
sonic anemometer head (CSAT3A), datalogger (CR3000), sample pump, and
an optional valve module for automated zero and span.
4.2.1 EC155 Gas Analyzer
The EC155 (FIGURE 4-16) is Campbell Scientific’s closed-path, mid-infrared
absorption gas analyzer that measures molar mixing ratios of carbon dioxide
and water vapor. More information about the operation of the EC155 can be
found in the manual, EC155 CO
2
and H
2
O Closed-path Gas Analyzer at
www.campbellsci.com .
FIGURE 4-16. EC155 gas analyzer
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