Campbell Scientific Sentek EnviroSCAN EasyAG SDI-12 Manual v 3.4 - Manual (Page 4)

EnviroSMART & EasyAG SDI-12 Probe Manual
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Table of Contents
The EnviroSMART® and EasyAG® SDI-12 Probe Interface .............................1
About the SDI-12 probe interface .......................................................................................................................1
What is SDI-12?.......................................................................................................................................................1
What are the EnviroSMART® and EasyAG® SDI-12 probe interfaces? ...................................................1
What is the Intelligent Probe Configuration Utility? ........................................................................................2
Setting the Probe Configuration ....................................................................................................................2
SDI-12 Probe Interface .........................................................................................4
About setting up the EnviroSMART® and EasyAG® SDI-12 probe interface.........................................4
Why do I need to configure the SDI-12 probe interface? ...............................................................................4
SDI-12 Communication........................................................................................5
About the SDI-12 Communication .....................................................................................................................5
Power Sequence.......................................................................................................................................................5
Timing .......................................................................................................................................................................6
Addresses..................................................................................................................................................................7
Data Reading............................................................................................................................................................8
Data Reading using the Start Measurement Command (aM! or aMn!)...................................................8
Data Reading using the Start Concurrent Measurement Command (aC! or aCn!).............................10
Identification..........................................................................................................................................................14
Supported Commands........................................................................................ 15
SDI-12 Commands Supported ...........................................................................................................................15
Extended Commands Supported .......................................................................................................................16
EnviroSMART® Technical Specifications ........................................................ 17
EasyAG® Technical Specifications ................................................................... 19
Circuit Information............................................................................................. 21
Revision Information..........................................................................................22
EnviroSMART® Revision Information............................................................................................................22
EasyAG® Revision Information........................................................................................................................22
Appendix A – Soil Moisture Management .........................................................23
What soil volume does the SDI-12 probe interface measure at a single sensor?.......................................23
What are the water units?.....................................................................................................................................23
What part of the soil profile do multiple sensors on the probe measure?..................................................24
Appendix B – Salinity Management...................................................................25