Xylem System 5000 Getting Started Guide User Manual
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System 5000™ Hardware
The Switched +12 volt excitation is provided to power sensors, and by default, this port is always on.
There are sensors that only need to be powered when being measured. To save power consumption,
this port can be programmed to turn on only during a measurement.
Switched +12 Volt Excitation
The Power connection is the main System 5000 power and ground. The power LED on the front
panel will blink every five seconds when power between 10 – 16 volts has been connected.
Power Connection
The lower right terminal strip is used for analog input functions. This includes four analog
inputs, two analog grounds, and one +5Vref excitation connection.
Analog Input Section
The AC Input is provided to connect sensors that have a low level AC output like wind speed
sensors. A wind speed sensor has at least two connections: Signal (ACIn) and Reference (Dgnd).
AC Input
The Digital I/O connections can be
configured independently as inputs or
outputs. In the input mode, the signal has
an internal pull up resistor of 47K Ohms.
This allows a switch closure to ground to
activate the input. It can also be driven
using normal logic levels. As an output,
a 100-Ohm protection resistor limits
the drive capability. The output will still
be about 4.0 volts with a 10.0mA or less
load. When a pair of digital I/O pins is
configured as inputs, they may be used as
a quadrature shaft encoder input.
Digital I/O