YSI WaterLog Series, Руководство пользователя

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Analog In
The Analog In input Channels are located on the lower second block of the front panel.
Surrounding the four channels are two ground channels (Agnd). The last port of the first block
contains the +5.00 volt switched excitation.
The four generic analog input channels are configured as single ended inputs with a default range
of 0.0 to 5.0 volts. A 5.00 volt switched excitation is also provided for sensors that require a
precision power reference. Differential readings may also be taken using Channels 1-2 or 3-4.
The Analog In Properties screen allows multiple options to be specified per Task, including the
Channel(s) to use, number of samples to take, and whether an excitation warmup should occur.
Channel: All four analog input Channels have a 0.0 to 5.0 Volt input range. As the internal
A/D has 24-bits of resolution, low level output voltage (0.0 to 500 mV) is inherently supported
and accurately measured on all channels. Both single-ended and differential measurements are
available by selecting either a single channel or the latter paired channels (1-2 or 3-4).
Many analog sensors send back a voltage on a single line that is referenced to ground. These are
called single ended sensors and are the simplest to work with. A simple wind direction sensor
that uses a continuous turn potentiometer is a good example of a single ended sensor.
A differential sensor will have two signal lines referenced to each other, not to ground. A strain
gauge is an example of a differential sensor. The two signal lines would be connected to analog
channels 1 and 2 or 3 and 4 and the corresponding Channels would be selected. The reading
System 5000
Inputs 5-3
TM