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Table of Contents
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Introduction ................................................................ 1
Precautions ................................................................ 1
Initial Inspection ......................................................... 1
QuickStart ................................................................... 1
Overview ..................................................................... 4
Specifications ............................................................. 5
Electrical Specifications ....................................................................... 6
Operational Specifications ................................................................... 7
Installation .................................................................. 8
Orientation and Placement ................................................................... 8
Datalogger Wiring................................................................................ 9
Operation .................................................................. 11
............................................. 11
Using the A200 ........................................................................... 11
Driver Installation ............................................................ 11
RS-232 Wiring ................................................................. 11
Powering the Sensor ......................................................... 12
Determining which COM Port the A200 has been
Assigned ....................................................................... 12
....................................................... 12
Settings Editor Tab ........................................................... 13
Send OS Tab..................................................................... 16
SDI-12 Measurements ........................................................................ 16
M3! and M4! Commands ............................................................ 17
Use of Multiplexers .................................................................... 19
Water Content Reflectometer Method for Measuring Volumetric
Water Content ................................................................................. 19
Description of Measurement Method.......................................... 19
Topp Equation............................................................................. 20
Electrical Conductivity ............................................................... 20
Soil Electrical Conductivity ............................................. 20
Temperature Correction of Soil Electrical
Conductivity ................................................................. 21
Error Sources in Water Content Reflectometer Measurement .... 21
Sensor-to-Sensor Variability Error ................................... 21