Campbell 110PV, Инструкция по эксплуатации

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Appendix B. Example Programs
B-3
B.1.2 4-Wire Half Bridge CR1000 Program
'CR1000 Series Datalogger
'This example program measures a single 110PV-L probe utilizing the
'BRHalf4Winstruction once a second and stores the
'average temperature in degrees C every 10 minutes.
'110PV-L Wiring Configuration
'Lead Color CR1000 Channel Description
'Black
VX1/EX1 Voltage Excitation
'Red DIFF1H Signal
'Purple DIFF1L Signal Reference
'Blue AG Signal Reference
'Green DIFF2H Sense +
'White DIFF2L Sense -
'Clear AG Shield
'Declare variables for temperature measurement using Half Bridge configuration
Public T110PV_mV
Public T110PV_Res
Public T110PV_Temp_C
Public T110PV_Temp_F
'Declare constants to be used in Steinhart-Hart equation
Const A=1.129241*10^-3
Const B=2.341077*10^-4
Const C=8.775468*10^-8
'Declare variable units
Units T110PV_mV= millivolts
Units T110PV_Res=Ohms
Units T110PV_Temp_C=Deg C
Units T110PV_Temp_F=Deg F
'Define a data table for 10 minute averages
DataTable (AvgTemp,1,1000)
DataInterval (0,10,Min,10)
Average (1,T110PV_Temp_C,FP2,False)
EndTable
BeginProg
Scan (1,Sec,3,0)
' Measure 110PV-L probe
BrHalf4W (T110PV_mV,1,mV2500,mV2500,1,Vx1,1,2500,True,True,0,_60Hz,1.0,0)
' Convert mV to ohms
T110PV_Res=4990 *T110PV_mV
' Use the Steinhart-Hart equation to convert resistance to temperature
T110PV_Temp_C = (1/(A+B*LOG(T110C*(LOG(T110PV_Res))^3))-273.15
'Convert Celsius to Fahrenheit
T110PV_Temp_F = T110PV_Temp_C * 1.8 + 32
CallTable AvgTemp
NextScan
EndProg