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
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,mV25C,1,True ,0,_60Hz,cnr4_mult(1),0)
'CNR4 thermistor measurement
BrHalf (Vs_Vx,1,mV2500,16,Vx2,1,2500,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
20