Campbell CS650, Product Manual

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8.3.3 Electrical conductivity 23
8.3.3.1 Soil electrical conductivity 23
8.3.3.2 Temperature correction of soil electrical conductivity 24
8.3.4 Error sources in water content reflectometer measurement 24
8.3.4.1 Sensor-to-sensor variability error 24
8.3.4.2 Insertion error 25
8.3.5 Temperature dependence and correction 25
8.3.5.1 Accurate soil temperature measurement 26
8.4 Water content reflectometer user-calibration 26
8.4.1 Need for soil specific calibration equation 26
8.4.2 User-derived calibration equation 26
8.4.3 Collecting laboratory data for calibration 27
8.4.4 Collecting field data for calibration 29
8.4.5 Calculations 32
9. Maintenance and troubleshooting 32
10. References 34
Appendix A. Importing Short Cut code into CRBasic Editor 35
Appendix B. Example programs 36
B.1 CR1000X with one CS650 sensor 36
B.2 CR1000X with two CS650 sensors on same control port 37
B.3 CR1000X with 12 CS650 sensors on multiplexer 38
Appendix C. Discussion of soil water content 40
Appendix D. SDI-12 sensor support 41
D.1 SDI-12 command basics 41
D.1.1 Acknowledge active command (a!) 42
D.1.2 Send identification command (al!) 42
D.1.3 Start verification command (aV!) 43
D.1.4 Address query command (?!) 43
D.1.5 Change address command (aAb!) 43
D.1.6 Start measurement commands (aM!) 43
D.1.7 Stopping a measurement command 44
D.1.8 Send data command (aD0! … aD9!) 44
D.2 SDI-12 transparent mode 45
D.2.1 Changing an SDI-12 address 45
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