Rockwell Automation 1756-RMxx ControlLogix Enhanced Redundancy System User Manual - Manual (Page 33)

Rockwell Automation Publication 1756-UM535D-EN-P - November 2012 33
Design an Enhanced Redundancy System Chapter 2
Plan for Communication Module Connections
A CIP connection is a point-to-point communication mechanism used to
transfer data between a producer and a consumer. These are examples of CIP
connections:
• Logix5000 controller message transfer to Logix5000 controller
• I/O or produced tag
• Program upload
• RSLinx DDE/OPC client
• PanelView™ polling of a Logix5000 controller
ControlLogix ControlNet communication modules provide 131 total CIP
connections. Consider these points when using CIP connections with
ControlLogix ControlNet communication modules:
• Three of the 131 CIP connections are reserved for redundancy. The three
redundant-system CIP connections always appear to be in use, even when
no connections are open.
• You can use the remaining 128 CIP connections in any manner that your
application requires, such as the examples listed above.
ControlLogix EtherNet/IP communication modules provide 259 total CIP
connections. Consider these points when using CIP connections with
ControlLogix EtherNet/IP communication modules:
• Three of the 259 CIP connections are reserved for redundancy.
• You can use the remaining 256 connections in any manner that your
application requires, such as the examples listed above.