Cr6 Program That Computes Vapor Pressure And Saturation Vapor Pressure - Campbell EE181 Instruction Manual

Appendix C. Absolute Humidity
'Clear: Shield - Ground Symbol
Public AirTC :
Public RH :
Public e_Sat :
Public e_kPa :
DataTable(Temp_RH,True,-1)
DataInterval(0,60,Min,0)
Average(1,AirTC,FP2,0)
Sample(1,RH,FP2)
Sample(1,e_kPa,IEEE4)
EndTable
BeginProg
Scan(5,Sec,1,0)
PortSet(9,1)
Delay(0,2,Sec)
'EE181 Temperature & Relative Humidity Sensor measurements
'AirTC and RH:
VoltSe(AirTC,1,mV2500,1,0,0,_60Hz,0.1,-40.0)
VoltSe(RH,1,mV2500,2,0,0,_60Hz,0.1,0)
PortSet(9,0)
'Calculate Saturation Vapor Pressure
SatVP(e_Sat, AirTC)
'Compute Vapor Pressure, RH must be a fraction
e_kPa = e_Sat * RH/100
CallTable(Temp_RH)
NextScan
EndProg
CRBasic Example C-2. CR6 Program that Computes Vapor Pressure and Saturation Vapor
Pressure
'Program measures EE181 with single-ended inputs once every 5 seconds
'and stores the average temperature and a sample of the relative
'humidity every 60 minutes.
'Wiring Diagram
'==============
'EE181
'Wire CR6
'Color: Function - Terminal
'------ -------- --------
'Red: Power - SW12-1
'Yellow: Temperature signal - U1
'Blue: Relative Humidity signal - U2
'Black: Power Ground - Ground Symbol
'Clear: Shield - Ground Symbol
Public AirTC :
Public RH :
Public e_Sat :
Public e_kPa :
DataTable(Temp_RH,True,-1)
DataInterval(0,60,Min,0)
Average(1,AirTC,FP2,0)
Sample(1,RH,FP2)
Sample(1,e_kPa,IEEE4)
EndTable
BeginProg
Scan(5,Sec,1,0)
SW12 (1,1 )
Delay(0,2,Sec)
C-2
Units AirTC = °C
Units RH = %
Units e_Sat = kPa
Units e_kPa = kPa
'Turn on switched 12V
'2-second delay
'Turn off switched 12V
Units AirTC = °C
Units RH = %
Units e_Sat = kPa
Units e_kPa = kPa
'Turn on switched 12V
'2-second delay