Campbell CS616, Instruction Manual

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CS616 and CS625 Water Content Reflectometers
'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=unco(Tref-Tsoil)*(t0+t1*uncot2*uncorrected^2)
vwc = a0 + a1*cor 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.
SE Chan : Enter the single-ended analog channel where the sensor’s green wire
is connected. When Reps is greater than 1, this entry is the channel for the first
CS616.
Port : Enter an integer to specify the control port that will be used to enable the
CS616 sensor. For the CR510, only C1 can be used to enable a CS616.
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