Comprehensive Stevens Hydra Probe II User's Manual
Table of Contents
1 Introduction 6
1.1 Applications.................................................................................................................................6
1.2 Temperature Corrections .............................................................................................................7
1.3 Calibrations..................................................................................................................................7
1.4 Dielectric Permittivity .................................................................................................................7
1.5 Structural Components ................................................................................................................7
1.6 Accuracy and Precision ...............................................................................................................7
2 Configurations of the Hydra Probe 8
2.1 Digital Probes ..............................................................................................................................8
2.1.1 Addressing & Programming...............................................................................................9
2.1.2 Daisy Chaining Versus Home Run Wiring ........................................................................9
2.1.3 SDI-12 Hydra Probe II .......................................................................................................9
2.1.3.1 Transparent Mode .....................................................................................................9
2.1.4 Digital RS-485 Hydra Probe II.........................................................................................10
2.1.4.1 Addressing and Programming ................................................................................10
2.2 Analog Hydra Probe ..................................................................................................................11
2.2.1 Analog Hydra Probe Output.............................................................................................11
2.3.2 Post possessing raw voltages into the measurements of interest...........................................12
2.2.2 Trouble Shooting the Analog Hydra Probe......................................................................13
2.3 Other Applications and Alternative Calibrations ......................................................................13
2.3.1 Frozen Soil .......................................................................................................................14
3Installation 15
3.1 Avoid Damage to the Hydra Probe:...........................................................................................15
3.1.1 Lightning ..........................................................................................................................15
3.2 Wire Connections ......................................................................................................................15
3.2.1 Analog Probe Wire Connection .......................................................................................15
3.2.2 SDI-12 Hydra Probe Wiring Connections........................................................................16
3.2.3 RS-485 Hydra Probe wiring Connections........................................................................16
3.3 Soil and Topographical Considerations....................................................................................17
3.3.1 Soil Moisture Calibration .................................................................................................17
3.3.2 Soil Classifications...........................................................................................................18
3.4 Installation of the Hydra Probe in Soil ......................................................................................19
3.4.1 Topography and Groundwater Hydrology .......................................................................19
3.4.2 Installation of the Hydra Probe into Soil..........................................................................21
3.4.3 Hydra Probe Depth Selection...........................................................................................22
3.4.4 Back Filling the Hole after the Probes are Installed.........................................................24
4 Measurements, Parameters, and Data Interpretation 26
4.1 Analog Hydra Probe Output ......................................................................................................26
4.1.1 Raw Voltages V1, V2, and V3.......................................................................................26
4.1.2 V4 .....................................................................................................................................26
4.1.3 V5 .....................................................................................................................................26
4.1.4 ADC Reading 1 through 5................................................................................................26
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