Campbell NR01, Инструкция по эксплуатации

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NR01 Four-Component Net Radiation Sensor
12
20 W m -2 or, if a measurement of air humidity is available, when the dewpoint
of the air falls to within 1 °C of the sensor body temperature. Appendix A.3 ,
CR3000 Program that Controls Heater
(p. A-6)
, provides an example
CR3000/CR5000 program that controls the NR01 heater.
6.5 Installation of the Radiation Shields
Radiation shields can be installed and removed using a hex-head wrench (bolt
size 2.0 mm). See the drawing below. Radiation shields are beneficial for
instrument measurement accuracy and instrument and cable lifetime. They
also serve as rain and snow shield. However, the instrument should function
within specifications without the radiation shield.
FIGURE 6-3. Installation and removal of radiation shields: (1) hex-head
wrench, (2) radiation screen, (3) hexagon drive set screw
6.6 Datalogger Programming
Programming basics for CRBasic dataloggers are provided in the following
sections. Equations used to calculate solar parameters and measurement details
are provided in Section 7 , Operation
(p. 13)
. Complete program examples for a
CRBasic datalogger can be found in Appendix A , Example Programs
(p. A-1)
.
Programming basics and programming examples for Edlog dataloggers are
provided at www.campbellsci.com/old-manuals .
6.6.1 Pyranometer/Pyrgeometer Measurements
The NR01 outputs four voltages that typically range from 0 to 50 mV for the
SR01 pyranometers, and
±
5 mV for the IR01 pyrgeometer. These voltages are
measured using either differential voltage measurements ( VoltDiff in CRBasic)
or single-ended measurements ( VoltSE in CRBasic). Differential voltage
measurements are recommended because they provide better noise rejection
than single-ended measurements.
If differential channels are not available, single-ended measurements can be
used. The acceptability of single-ended measurements can be determined by
comparing the results of single-ended and differential measurements made
under the same conditions.