Campbell NR01, Инструкция по эксплуатации

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NR01 Four-Component Net Radiation Sensor
20
8.2 Troubleshooting
8.2.1 Data Quality Assurance
To assure quality data, look for unrealistic values when analyzing:
•
Trends in SW
in
absolute signal
• SW albedo
• Correlation of SW
in
and LW
in
•
SW night time signals
• Correlation of relation LW
out
and surface temperature
8.2.2 Problem Diagnosis
TABLE 8-2 contains information used to diagnosis problems whenever the
sensor does not function properly.
TABLE 8-2. Troubleshooting for the NR01
The sensor does
not give any
signal
Typically an error is due to either a short circuit or an
open connection. Both can be detected by impedance /
resistance measurements at the cable end.
In case of open circuits: open the instrument and check
the internal connections (see TABLE B-3 ).
The sensor signal
is unrealistically
high or low
Check if the right calibration factors are entered into the
algorithm. Please note that each sensor has its own
individual calibration factor.
Check if the voltage reading is divided by the
calibration factor by review of the algorithm.
Check the condition of the leads at the datalogger.
Check the cabling condition looking for cable breaks.
Check the data acquisition by applying an mV source to
it in the 1 mV range.
Perform a sensor-inversion test (see Section
6.7 ,
Instrument-Inversion Test
(p. 13)
).
Open the instrument and check the internal connections
(see TABLE B-3 ).
The sensor signal
shows
unexpected
variations
Check the presence of strong sources of
electromagnetic radiation (radar, radio etc.).
Check the condition of the shielding.
Check the condition of the sensor cable.
Open the instrument and check the internal connections
(see TABLE B-3 ).