Rockwell Automation 1756-RMxx ControlLogix Enhanced Redundancy System User Manual - Manual (Page 15)

Rockwell Automation Publication 1756-UM535D-EN-P - November 2012 15
Chapter
1
About Enhanced Redundancy Systems
The ControlLogix Enhanced Redundancy System is a system that provides
greater availability because it uses a redundant chassis pair to maintain process
operation when events, such as a fault on a controller, occur that stop process
operation on nonredundant systems.
The redundant chassis pair includes two synchronized ControlLogix chassis with
identically specific components in each. For example, one redundancy module
and at least one ControlNet or EtherNet/IP communication module are
required.
Controllers are typically used in enhanced redundancy systems, but are not
required if your application only requires communication redundancy. Your
application operates from a primary chassis, but can switch over to the secondary
chassis and components if necessary.
Topic Page
Features of the ControlLogix Enhanced Redundancy System 16
Enhanced Redundancy System Components 17
Enhanced Redundancy System Operations 19
Restrictions 22