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SDI-12 Parameter-Driven Sampling
In this sampling scenario, the ProSample will collect samples based upon measurements from an SDI-12 device (
e.g.
YSI EXO3 sonde). This sampling scenario can only be completed with the ProSample P-12 and ProSample PM-12.
Please refer to the
section on page 26 when connecting the SDI-12 device to the ProSample.
In order to use an SDI-12 device, the user must configure it properly before programming the ProSample P-12 or
ProSample PM-12. As an example, if pH is a trigger parameter, the pH channel on the sonde and the ProSample must
be the same (
e.g.
channel 1). Please consult the user manual of your SDI-12 device regarding proper configuration.
Up to 4 SDI-12 parameters can be configured to trigger sampling. If there is a need for an AND scenario with multiple
parameters to trigger sampling (
e.g.
solution must have pH > 8
AND
turbidity >124 FNU for sampling to begin), then a
data logger must be used to trigger sampling (see
There are two different methods of programming the sampler to stop sampling – continuous method and event
method. Steps # 9 and 12 in the following procedure determine which method is utilized.
Continuous method
: If the trigger criteria are met, sampling will occur until the program is complete, even if the
trigger criteria are no longer met while the program is active. If more than one SDI-12 parameter is set to trigger
sampling, only the continuous method can be used.
Event method
: Sampling will only occur when the trigger criteria are met. If the trigger criteria are no longer met while
the program is active, sampling will pause. Sampling will continue if and when the trigger criteria are met again and
will continue until the program is complete.
NOTE:
The settings modified in the section
Configure Key Instrument Settings
on page 22 will be applied to each
and every program, so it is important these settings are carefully set before starting any program.
NOTE:
Screenshots demonstrate an example setup. Settings should be adjusted for your specific application.
The following procedure should be followed for each SDI-12 parameter (up to 4) that will be used to trigger sampling.
NOTE:
If using the continuous method, it is recommended to program the sampler (i.e. follow the procedure
below), place the SDI-12 device in the sampling environment, and then connect the SDI-12 device to the
ProSample P-12 or ProSample PM-12. This is recommended because the program is automatically started
if the trigger criteria are met (i.e. the program is not started by going to
Program
g
Start
).
1.
From the Main Menu, select
Setup
g
System Settings
g
Measurement Input
.
2. Trigger (CH)
is displayed. Use the right arrow key to select the
trigger channel to configure. Press the Enter key to configure
this channel.
NOTE:
Select a different trigger channel for each SDI-12
parameter that will be used to trigger sampling.
Programming: SDI-12 Parameter Driven Sampling