YSI WaterLog Series, Owner'S Manual

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of connecting multiple SDI-12 sensors. Standard SDI-12 sensors have a minimum of three
wires: +12V, Data, and Gnd.
The SDI-12 Sensor Input allows the System 5000 to communicate with and retrieve
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measurement parameters from a standard SDI-12 sensor. The options on the screen combine to
retrieve the requested data. For example, in the above screen, a command of “0M” would first be
sent, the reply would be received and parsed, the necessary time would be delayed and then the
data values would be retrieved. In this case, the first sdi-12 parameter would be recorded. Due
to the possible long length of time needed for SDI-12 Measurements, the SDI-12 Value can be
manually retrieved via the Test button and does not continuously retrieve the data. Once a Test
has been started the measurement can be aborted by pressing the Abort button, which is shown
once the Test has begun.
Sensor Address: Defines the sensor address to query. Addresses can be any single digit number
or letter. Sensor addresses are case-sensitive, thus sensor H is different from sensor h. Most
sensors typically use a number for their address. Finding unknown sensor addresses as well as
changing current addresses can be done within the SDI-12 Transparent Mode.
Measurement CMD: Defines the measurement command to use when querying the SDI-12
Sensor. Available commands are M, R, C, MC, RC, CC, and D with an optional number
specified after the command (e.g. M1, MC2, etc).
SDI-12 Parameter: Defines the parameter to record after receiving the measurement data. A
value of 5, for example, will return the fifth value received from the Data command after a
standard Measure command. All necessary waiting and available parameters will be interpreted
and received by the System 5000 .
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Transparent Mode: The built-in SDI-12 Transparent Mode, discussed more in Chapter 11,
allows all SDI-12 communication (to/from the System 5000 as well as from other sensors on
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the sdi-12 line) to be seen. Pre-defined as well as custom/extended SDI-12 commands can be
issued from within the Transparent Mode.
5-12 Inputs
System 5000
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