Rockwell Automation 1755-OF8 GuardPLC Controller Systems - Manual (Page 83)

83 Publication 1753-UM001C-EN-P - March 2010 83
Chapter
8
Wire and Configure the 1753-IB16XOB8
Module
Introduction
The module features 16 digital inputs, 8 two-pole (8
positive-switching and 8 negative-switching) digital outputs, and 2
pulsed outputs.
Safety-related Digital
Inputs The status of digital inputs is indicated via status indicators when the
module is in Run mode.
LS+ is a voltage source that provides 24V DC for a group of four
inputs. There are four groups on the module. If devices require
24V DC to operate and use the same power source as the GuardPLC
module, wire the outputs of the device directly to inputs on the
GuardPLC module. Devices with their own dedicated power supply
can also be connected instead of contacts. Connect the reference pole
of the signal source to the L- reference pole of the input. See the
wiring diagrams in
Appendix C for examples.
The safety state of an input is indicated by a 0 signal being passed to
the user program logic. If the test routines detect a fault in the digital
inputs, a 0-signal is processed in the user program for the defective
channel. When a fault occurs, the inputs are switched off (0) and the
fault status indicator is activated.
The sensor supplies, LS+, supply a default current of 40 mA that is
buffered for 20 ms in case of a power failure. If a higher current is
needed, two unbuffered supplies of 1 A can be switched on by using
the DI Supply [xx] system signal in the application program. This
supply feeds the neighboring input channel group. The status of this
Topic Page
Safety-related Digital Inputs 83
Safety-related Digital Outputs 86
Monitor for Line Short Line Break 91
Pulse Test Sources 93