Campbell Scientific 110PV Surface Temperature Probe - Manual (Page 21)

110PV Surface Temperature Probe
'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(T110PV_Res)+C*(LOG(T110PV_Res))^3))-273.15
'Convert Celsius to Fahrenheit
T110PV_Temp_F = T110PV_Temp_C * 1.8 + 32
CallTable AvgTemp
NextScan
EndProg
5.2 Edlog
In Edlog, Instruction 5 is typically used to measure the 110PV-L. The ratio
metric output is then converted to resistance and finally to temperature (see
Section 5.2.1).
5.2.1 Example Edlog Program
TABLE 5-2. Wiring for Example Program
Color Description CR10X
Black Voltage Excitation E1
Red Signal SE1
Purple Signal Reference AG
Clear Shield G
Blue Not Used Not Used
Green Not Used Not Used
White Not Used Not Used
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