Features specific to fast output modules, Programmable fault state delays – Rockwell Automation 1756-XXXX ControlLogix Digital I/O Modules User Manual
Page 95
Rockwell Automation Publication 1756-UM058G-EN-P - November 2012
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Fast Module Features
Chapter 5
Features Specific to
Fast Output Modules
The table below lists features specific to ControlLogix fast digital output
modules.
Programmable Fault State Delays
You can define the following states for an output point that is in Fault mode due
to a communication failure:
•
Duration—Defines the length of time that the output remains in the Fault
mode state before transitioning to a final state of On or Off. By default, the
output remains in the Fault mode state as long as the fault condition
persists.
•
Final state—Defines whether the output transitions to the On or Off state
after the duration of the Fault mode state elapses. By default, the output
transitions to the Off state.
Topic
Page
Programmable Fault State Delays
Peer I/O Control (1756-OB16IEF only)
See the Peer I/O Control Application Technique,
publication
IMPORTANT
In RSLogix 5000 software, version 18.02.00 and 19.01.00, output tag
information is sent to the 1756-OB16IEF module only at the RPI rate defined
during configuration. For optimal performance, use an Immediate Output (IOT)
instruction.
For example, the rung shown below contains an IOT instruction for a fast
output module in slot 3. Add a similar rung to your last routine within the Main
Task to mimic normal output tag processing.
EXAMPLE
You define a duration of 1 second and a final state of On for an output point. If a
fault occurs at that point, the output remains in its Fault mode state (Off, On, or
Hold) for 1 second before transitioning to the On state.
IMPORTANT
If a connection is reestablished after an output point goes into Fault mode but
before the duration time elapses, the settings you specify for the duration and
final state no longer apply. For example, if you specify a 10 second duration and
a final state of Off, and the fault ends in 3 seconds, the output point never
transitions to the final state of Off.