Campbell Scientific CPEC200 Closed-Path Eddy-Covariance System - Manual (Page 17)

CPEC200 Closed-Path Eddy-Covariance System
FIGURE 4-9. CSAT3A sonic anemometer head
4.1.2.5 Barometer
The EC100 is always configured with an EC100 basic barometer. However, an
EC100 enhanced barometer is available as an option. The decision to upgrade
to the enhanced barometer is largely dependent on the specific site and
environmental constraints for a given site. In general, the enhanced barometer
provides overall greater accuracy, but may not be a necessary upgrade for
many applications.
Unlike open-path systems, the accuracy of the CPEC200 system is influenced
by the sample cell pressure. The EC155 sample cell pressure is measured by a
differential pressure sensor that measures the sample cell pressure relative to
barometric pressure (as measured by the EC100 barometer). The accuracy of
the sample cell pressure measurement is the sum of the accuracy of the
barometer in the EC100 and the differential pressure sensor in the EC155.
The measurement rate is likewise affected by both the sample cell pressure and
the specific barometric pressure of the barometer – either basic or enhanced.
The differential pressure sensor is always measured at 10 Hz, while the basic
barometer is measured at 10 Hz and the enhanced barometer is measured at 1
Hz.
For greater detail, see Section 4.3, Specifications, of this manual or consult a
Campbell Scientific applications engineer for specific sites and applications.
4.1.2.6 Carrying Cases
The EC155 and the CSAT3A may be ordered with optional carrying cases. If
the carrying cases are not ordered, the sensors are shipped in cardboard boxes.
4.1.2.7 Enclosure Mounting Options
The CPEC200 system enclosure and the CPEC200 pump module can be
configured with one of several mounting options. The CPEC system enclosure
is similar to the Campbell Scientific ENC16/18 enclosure, and the CPEC200
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