Xylem System 5000 User Manual - Manual (Page 14)

12
HARDWARE OVERVIEW
If more options are needed in addition to the base configuration of the System 5000
™
, option
cards/modules can be used to quickly and simply expand the functionality of the unit. Three
expansion slots allow any combination of the plug-in modules below to be added or removed
when needed, whether when initially ordered or in the field.
Option Cards
Analog / Digital Expansion Module
The 4-20mA output connection points are at
the far right of the lower terminal strip. Several
instrumentation applications use sensors that
provide an industry standard 4-20 milliamp output
signal. The System 5000
™
data logger / DCP
can output a 4-20mA signal based on any of its
inputs. For example, a user may want to connect
a temperature probe to the System 5000
™
and
convert the temperature value into a 4-20mA
output. A temperature probe on Analog Channel
1 that produces a 0 to 5 volt output representing
0 to 100 degrees Celsius could easily be setup to
produce a 4-20 mA output that represents the 0 to
100 degrees. The System 5000
™
does not actually
output a 4-20mA signal, but rather controls the
current in an isolated externally powered loop.
The following figure shows a basic connection
diagram.
4 to 20 Milliamp (4-20mA) Output
The +5Vref output is used for analog sensors requiring a precision reference voltage. The maximum
output current is 10 milliamps. The Analog to Digital converter uses this excitation for
its reference to provide a ratio-metric relationship for sensors using this excitation.
Switched +5.00 Volt Reference Excitation
The Analog/Digital Expansion Module provides a generous expansion to the built-in analog and
digital ports available on a base System 5000
™
unit. An RS-232 serial port is also provided for
additional serial connectivity and communications. The module includes two digital grounds, an
AC-In, four digital I/O ports, a +5V reference, a 4-20 milliamp output, two analog grounds, an AC-In,
four digital I/O ports, a +5V reference, a 4-20 milliamp output, two analog grounds, and eight analog
channels that can be used as four differential channels.