Specifications
Table Of Contents
- Revision and Copyright Information
- Warranty and Assistance
- Table of Contents
- CNR4 Net Radiometer
- 1. General Description
- 2. Sensor Specifications
- 3. Installation
- 4. Using the Optional CNF4 Heater/Ventilator Unit
- 5. Using the CNR4 in the Four Separate Components Mode
- 5.1 Measuring Short-wave Solar Radiation with Pyranometer
- 5.2 Measuring Long-wave Far Infrared Radiation with Pyrgeometer
- 5.3 Measuring CNR4 Temperature with Thermistor
- 5.4 Calculation of Albedo
- 5.5 Calculation of Net Short-wave Radiation
- 5.6 Calculation of Net Long-wave Radiation
- 5.7 Calculation of Net (Total) Radiation
- 6. Wiring
- 7. Datalogger Programming
- 8. Troubleshooting
- 9. Maintenance and Recalibration
- Appendix A. CNR4 Performance and Measurements under Different Conditions
- Appendix B. CNF4 Heater/Ventilator
- Appendix C. CR3000 Program for Measuring Pt-100 Temperature Sensor
- Campbell Scientific Contact Information

CNR4 Net Radiometer
'CNR4 multipliers
Public cnr4_mult(4)
Const pyranometer_up_mult = 1000/pyranometer_up_sensitivity '(W/m^2/mV)
Const pyranometer_dn_mult = 1000/pyranometer_dn_sensitivity '(W/m^2/mV)
Const pyrgeometer_up_mult = 1000/pyrgeometer_up_sensitivity '(W/m^2/mV)
Const pyrgeometer_dn_mult = 1000/pyrgeometer_dn_sensitivity '(W/m^2/mV)
DataTable (cnr4_data,True,-1)
DataInterval (0,60,Min,10)
CardOut (1,-1)
Minimum (1,batt_volt,FP2,0,False)
Sample (1,logger_temp,FP2)
Average (4,cnr4(1),IEEE4,False)
Average (1,cnr4_T_C,IEEE4,False)
Average (1,cnr4_T_K,IEEE4,False)
Average (1,long_up_corr,IEEE4,False)
Average (1,long_dn_corr,IEEE4,False)
Average (1,Rs_net,IEEE4,False)
Average (1,Rl_net,IEEE4,False)
Average (1,albedo,IEEE4,False)
Average (1,Rn,IEEE4,False)
EndTable
DataTable (cnr4_ts,True,-1)
DataInterval (0,1,Sec,10)
CardOut (1,-1)
Sample (4,cnr4(1),IEEE4)
Sample (1,cnr4_T_K,IEEE4)
EndTable
BeginProg
'Load the multiplier values for the CNR4
cnr4_mult(1) = pyranometer_up_mult
cnr4_mult(2) = pyranometer_dn_mult
cnr4_mult(3) = pyrgeometer_up_mult
cnr4_mult(4) = pyrgeometer_dn_mult
Scan (1,Sec,3,0)
PanelTemp (logger_temp,250)
Battery (batt_volt)
'CNR4 radiation measurements
VoltDiff (cnr4(1),4,mV20C,1,True ,0,_60Hz,cnr4_mult(1),0)
'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
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