Appendix B. CNF4 Heater/Ventilator
B-9
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)
P
anelTemp (logger_temp,250)
B
attery (batt_volt)
'CNR4 radiation measurements
'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 = c273.15
'Correct the long-wave radiation values from pyrgeometers
long_up_corr = 5.67e-8*cnr4_T_K^4
long_dn_corr = 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 = Rl_net
'CNF4 ventilator control - the ventilator will be turned on when flag(1) is set high
SW12 (1,flag(1))
VoltDiff (cnr4(1),4,mV20C,1,True ,0,_60Hz,cnr4_mult(),0)