Campbell Scientific TDR100 Time Domain Reflectometry Systems - Manual (Page 28)

TDR100
6.3.2.2 Enter 1: Collect Waveform
The digitized reflection waveform can be collected from the TDR100 by the
datalogger in ASCII format. Datalogger input storage must be manually
allocated for the waveform data points using “block allocation” in Edlog
datalogger software. The waveform is collected as an array. The first 9 cells
of the array is a header and contain values entered in Instruction 119.
Waveform values fill the rest of the array. Always allocate 9 more cells in
datalogger input storage than the number of datapoints chosen in parameter 6.
See Section 6.2.11.1 for header information.
6.3.2.3 Enter 2: Collect Waveform and First Derivative
The reflection waveform and the first derivative are written to datalogger input
storage. Input storage must be manually allocated. See Section 6.2.6. The
required number of input locations is twice the number of points (Instruction
119, parameter 6) plus 9 for the header information.
6.3.2.4 Enter 3: Measure Bulk Electrical Conductivity
The electrical conductivity routine in the datalogger returns the value
1 1
1 Z
c
− ρ
+ ρ
which must be multiplied by the probe constant, K
p
, to get an electrical
conductivity value. Kp is entered in Instruction 119 parameter 12. See
Section 7 for discussion of the electrical conductivity measurement method and
Section 6.2.13.1 for discussion of Kp..
6.3.3 Parameter 3: Multiplexer and Probe Selection
Addressing scheme: ABCn
Where:
A -- Level 1 multiplexer channel
B -- Level 2 multiplexer channel
C -- Level 3 multiplexer channel
n -- the number of consecutive probes; addressing starts with the channel
specified for the highest level multiplexer.
Note: enter a 0 when a level is not used.
Example 1
An entry of 1008:
Entry Description
1 channel 1 is specified for the level 1 multiplexer.
0 the level 2 multiplexer is not used.
0 the level 3 multiplexer is not used.
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