5604 Input/Output (I/O) Module - Hardware Manual
October 19, 2007
7 Digital I/O
The 5604 I/O module has 32 universal digital inputs/outputs. Each digital I/O point can be used as
an input or an output only. The inputs can be used to monitor the status of that output.
The 32 I/O points are organized into four groups of eight. Four connectors are used for wiring the
digital inputs/outputs. These connectors are identified as P6 through P9. Refer to figure_37Figure
1: 5604 I/O Module Layout for the location of these connectors.
In addition to the 32 universal digital input/outputs there are 3 internal digital inputs and 2 internal
digital outputs that are used to monitor and control the DC/DC converter or VLOOP power supply
as well as to monitor digital output mismatch status. Refer to section 7.3-Internal DIO for
information on these internal digital I/O.
For TelePACE applications use the SCADAPack 5604 I/O Module register assignment to read
the digital inputs and write the digital outputs.
For ISaGRAF applications use the sp5604 I/O connection to read digital inputs and write the
digital outputs.
Please refer to the respective TelePACE and ISaGRAF software manuals on how to assign the above
registers to read these input ports.
7.1 Digital Inputs
The inputs are intended for use with dry contacts such as switches, open collector transistors and
relay contacts. Wetting current for the contacts is provided. The input is connected from the I/O
terminal to the terminal labeled GND. All GND terminals are connected internally to the
SCADAPack chassis.
If LED power is enabled, there is a continuous 5mA wetting current for each input. Indicator LED’s
will be at their maximum brilliance if on. This facilitates field service and diagnostics.
If LED power is disabled then the wetting current is turned on only when the digital inputs are
scanned. Power consumption is reduced as the inputs are scanned only once every millisecond.
Indicator LED’s are dim in this condition. This is normal.
7.2 Digital Outputs
Outputs are open-collector/open drain type for use with sustained DC loads of up to 1 ampere.
Loads with high in-rush currents may exceed the 1A rating. The output circuit will tolerate these
higher peak currents. The load is connected between this output point and a +DC power source. The
negative side of the DC power source must be connected the terminal labeled GND. All GND
terminals are connected internally to the SCADAPack chassis. This is the return path from –DC to
the load.
Inductive load transient suppression is built into each digital output point. It is not necessary to add
additional inductive load transient suppression unless highly inductive loads (greater than 1H) are
operated continuously at greater than 0.5Hz.
7.3 Internal DIO
The 5604 I/O Module also provides internal digital outputs to enable the DC/DC boost converter, to
switch on/off the boost converter output and control the analog input filtering. Theses digital outputs
can be controlled by the user application to manage power savings and control the analog input
response.
To Next Page
Loading...