Rockwell Automation 1732E-OB8M8SR EtherNet/IP Dual Port 8-Point SOE Input and Scheduled Output Modules UM - Manual (Page 20)

10 Rockwell Automation Publication 1732E-UM003B-EN-E - March 2014
Chapter 2 Module Overview and Features
• Used in SCADA applications to indicate pump failures or other discrete
events
• Used in motion control applications to increase control coordination.
• Used in high speed applications
• Used in Global Position Registration
In today's environment, specifications for SOE applications typically require 1 ms
or better resolution on timestamps. There are two types of SOE applications.
• First Fault – measures the time between events with no correlation to
events outside of that system.
• Real Time – captures the time of an event occurrence as it relates to some
master clock. Typically this is a GPS, NTP server or some other very
accurate clock source. This method allows distributed systems to capture
events and build a history of these events. These events are almost always
digital, however some are analog for which lower performance
requirements can be configured.
First Fault Detection
An example of first fault detection would be intermittent failure from a sensor on
a safety system faults a machine and halts production cascading a flood of other
interrelated machine faults. Traditional fault detection or alarms may not appear
in the correct timed order of actual failure making root cause of the down time
difficult or impossible.
Time Stamped I/O
High precision timestamps on I/O allows very accurate first fault detection
making it easy to identify the initial fault that caused machine down time.
Common Time base for Alarming System logs user interaction as well as alarm
events using common time reference.
The power industry requires sub 1 ms accuracy on first fault across geographically
dispersed architecture.
High Speed Applications
Packaging machines or sorters that have fast part cycles are often bottlenecked by
controller scan times. By switching to a time-based solution, you can remove
many scan time critical components of the system. This programming technique
allows you to do predictive events and schedule outputs to run things like
diverters without having a scan time to match the part cycle time.