Campbell Scientific CS616 and CS625 Water Content Reflectometers - Manual (Page 19)

CS616 and CS625 Water Content Reflectometers
'CR200(X) program to read 1 109 temperature probe and 1 CS625.
'Use temperature to correct CS625 period.
'Standard calibration is used to convert CS625 output
'period to volumetric water content.
'Sensors are read hourly and average water content and
'temperature are written to storage every 4 hours.
'Declare Variables
Public Tsoil
Public uncorrected,corrected
Public vwc
'Declare Constants
'Water content calibration constants
Const a0=-0.0663
Const a1=-0.0063
Const a2=0.0007
'Temperature correction constants
Const t0=0.526
Const t1=-0.052
Const t2=0.00136
'Reference temperature
Const Tref=20
'Define Data Tables
DataTable (ofile,1,10)
DataInterval (0,4,hr)
Average(1,Tsoil,0)
Average (1,vwc,0)
EndTable
'Main Program
BeginProg
Scan (1,hr)
Therm109 (Tsoil,1,5,Ex1,1.0,0)
SWBatt (1)
PeriodAvg (uncorrected,1,0,10,10,C1,1,0)
SWBatt (0)
corrected=uncorrected+(Tref-Tsoil)*(t0+t1*uncorrected+t2*uncorrected^2)
vwc = a0 + a1*corrected + a2*corrected^2
CallTable ofile
NextScan
EndProg
6.4.4 Measuring CS616 Using Edlog
6.4.4.1 Using Edlog Instruction 138
See Section 6.4.5.1, CS616 Sample Edlog Program 1, for example on using
Instruction 138.
1: CS616 Water Content Reflectometer (P138)
1: 1 Reps
2: 00 SE Channel
3: 00 Control Port Code
4: 0000 Loc [ _________ ]
5: 1.0 Mult
6: 0.0 Offset
Reps: Enter the number of CS616s that will be measured with the instruction.
The sensors must be wired in consecutive channels. Each measurement uses
the same multiplier and offset. The option chosen in parameter 3 will
determine whether subsequent repetitions are enabled with the next higher
control port or with the same control port.
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