Campbell CMP11-L, Инструкция по эксплуатации

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CMP6-L, CMP11-L, and CMP21-L Pyranometers
5. Overview
5.1 Models
CMP-series models differ in accuracy and performance. See Section 6,
Specifications . The CMP21 also includes an internal thermistor allowing
individually optimized compensation of the measurements. The –L portion of
the model number indicates that the pyranometer has a user-specified cable
length. The pyranometers have several cable termination options. Their cables
can terminate in:
•
Pigtails that connect directly to a Campbell Scientific datalogger
(cable termination option –PT).
•
Connector that attaches to a prewired enclosure (cable termination
option –PW).
•
Connector that attaches to a CWS900 Wireless Sensor Interface (cable
termination option –CWS). The CWS900 enables the pyranometer to
be used in a wireless sensor network. Please note that this option is
not available for the CMP21.
5.2 Construction
The pyranometers consist of a thermopile sensor, housing, two glass domes,
and cable. The thermopile is coated with a black absorbent coating. The paint
absorbs the radiation and converts it to heat. The resultant temperature
difference is converted to a voltage by the copper-constantan thermopile. The
thermopile is encapsulated in the housing in such a way that it has a field of
view of 180 degrees and the angular characteristics needed to fulfill the cosine
response requirements.
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