Campbell CNR4, Руководство по эксплуатации продукта

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CNR4 Net Radiometer
5
domes and windows to minimize the formation of dew and to reduce the
frequency of cleaning. The integrated heater can be used to melt frost.
The CNR4 design is such that both the upward facing and the downward-
facing instruments measure the energy that is received from the whole
hemisphere (180° field of view). The output is expressed in W/m
2
. The total
spectral range that is measured is roughly from 0.3 to 42 μ m. This spectral
range covers both the short-wave solar radiation, 0.3 to 2.8 μ m, and the long-
wave far infrared radiation, 4.5 to 42 μ m. The gap between these two produces
negligible errors.
The CNR4 is manufactured by Kipp & Zonen, but cabled for use with
Campbell Scientific data loggers.
6. Specifications
Features:
•
Research-grade performance
• Meniscus dome on upper long-wave detector allows water droplets to
easily roll off of it and increases field of view to nearly 180°
•
Internal temperature sensors provide temperature compensation of
measurements
•
Drying cartridge helps keep the electronics dry
• Compatible with the CNF4 ventilation unit with heater that reduces
formation of dew and melts frost
•
Separate outputs of short-wave and long-wave infrared radiation for
better accuracy and more thorough quality assurance
•
Solar shield reduces thermal effects on the sensors
•
Compatible with Campbell Scientific CRBasic data loggers: CR6
series, CR1000X, CR1000, CR3000, and CR5000
The properties of the CNR4 are mainly determined by the properties of the
individual probes. Generally, the accuracy of the CNR4 will be higher than that
of competitive net-radiometers, because the solar radiation measurement
performed by the pyranometer is accurate, and offers a traceable calibration.
Also the optionally integrated heater/ventilator unit improves the accuracy.
Due to the fact that the net short-wave radiation can be very intense, 1000
W/m
2
compared to a typical –100 W/m
2
net long-wave radiation, the accuracy
of the short-wave radiation measurement is critical. Wind corrections, as
applied by less accurate competitive instruments are not necessary. The robust
materials used imply that the CNR4 will not suffer damages inflicted by birds.
FIGURE 6-1 and FIGURE 6-2 show the CNR4 with and without the CNF4
heater/ventilator. From a spectral point of view, the pyranometer and
pyrgeometer are complementary, and together they cover the full spectral
range.