Campbell Scientific CNR4 Net Radiometer - Manual (Page 35)

CNR4 Net Radiometer
'CNR4 thermistor measurement
BrHalf (Vs_Vx,1,mv5000,16,Vx1,1,2500,True ,0,250,1.0,0)
Rs = 1000*(Vs_Vx/(1-Vs_Vx))
cnr4_T_C = 1/(1.0295e-3+2.391e-4*LN(Rs)+1.568e-7*(LN(Rs))^3)-273.15
'Convert CNR4 temperature to Kelvin
cnr4_T_K = cnr4_T_C+273.15
'Correct the long-wave radiation values from pyrgeometers
long_up_corr = long_up+5.67e-8*cnr4_T_K^4
long_dn_corr = long_dn+5.67e-8*cnr4_T_K^4
'Compute short-wave net radiation
Rs_net = short_up - short_dn
'Compute long-wave net radiation
Rl_net = long_up - long_dn
'Compute albedo
albedo = short_dn/short_up
'Compute net radiation
Rn = Rs_net + Rl_net
CallTable cnr4_data
CallTable cnr4_ts
NextScan
EndProg
7.3. m Using Differential Measurements
ur differential channels to measure the four radiation
n channel, and one single-ended channel to measure the
easures the sensors every 1 second, performs the
a, and stores the following processed data to a data
ta once every 60 minutes. It also stores the raw time-series
data table called cnr4_ts.
The variables for the CR5000 datalogger can be up to 16
2.3 Example 3, CR5000 Progra
Example 3 requires fo
outputs, one excitatio
thermistor. The program m
online processing of the dat
table called cnr4_da
data from CNR4 to
characters in length. However, if the variable is processed in the
output type other than Sample, the name will
d in the datalogger to 12 characters, plus an
nd a 3 digit suffix indicating the output type (for
example, _avg, _max).
output table by an
be truncate
underscore a
Minimum battery voltage
Sample datalogger panel temperature
tion (pyranometer up)
tion (pyranometer down)
Average long-wave radiation (pyrgeometer up)
long-wave radiation (pyrgeometer down)
Average CNR4 thermistor temperature (degrees C)
Average CNR4 thermistor temperature (Kelvin)
n)
Average short-wave net radiation
Average long-wave net radiation
Average albedo
Average net radiation
Average short-wave radia
Average short-wave radia
Average
Average corrected long-wave radiation (pyrgeometer up)
Average corrected long-wave radiation (pyrgeometer dow
NOTE
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