1 calibration factor, 2 example programs, 1 example 1, cr1000 using differential channels – Campbell Scientific CNR1 Net Radiometer User Manual
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CNR1 Net Radiometer
FIGURE 6-1. 4WPB100 Module
6.1 Calibration Factor
Each CNR1 is provided with a ‘Certificate of Calibration’ by the manufacturer
that shows the sensor serial number and ‘sensitivity’, or calibration factor. The
serial number and sensitivity are also shown on a label attached to the sensor.
The calibration factor is in units of
μV/(W m
-2
), which needs to be converted to
units of (W m
-2
)/mV for the multiplier parameter in the datalogger program.
To convert the units, divide the calibration factor into 1000. For example, if
the calibration factor is 7.30
μV/(W m
-2
), the multiplier is 1000/7.3 = 136.99
(W m
-2
)/mV.
6.2 Example Programs
6.2.1 Example 1, CR1000 Using Differential Channels
Program Example 1 requires six differential channels and the 4WPB100
module to measure the four radiation outputs and the Pt-100 temperature
sensor. The program measures the sensors every 2 seconds and calculates and
stores the following data to final storage every 60 minutes:
Year
Julian
Day
Hour/Minute
Avg CM3 Up (shortwave radiation)
Avg CM3 Down (shortwave radiation)
Avg CG3 Up (longwave radiation)
Avg CG3 Down (longwave radiation)
Avg CNR1 temperature (degrees C)
Avg CNR1 temperature (degrees K)
Avg Net shortwave radiation
Avg Net longwave radiation
Avg
Albedo
Avg Total Net radiation
Avg temperature corrected CG3 Up
Avg temperature corrected CG3 Down
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