User Manual Owner manual
30 Rockwell Automation Publication 1715-UM001C-EN-P - March 2014
Chapter 1 Redundancy System Overview
For a STAR Topology, the adapter modules’ Ethernet ports are configured with
the leftmost ports (Port 1 of Module A and Port 1of Module B) operating as a
2-port switch. The rightmost ports on each adapter are left unused.
Figure 10 - STAR Ethernet Topology
For Ethernet considerations, see EtherNet/IP Modules in Logix5000 Control
Systems, publication ENET-UM001
, and ControlLogix Enhanced Redundancy
System, publication 1756-UM535
.
Communication on the EtherNet/IP Network
Communication to a simplex module is addressed to the slot number for that
module. CIP communication to modules in a duplex configuration (including
the adapter modules) are addressed to the lowest slot number for the module pair.
The adapter modules respond with CIP errors for attempts to communicate to
an I/O module of a type that is not the same as the physically installed module.
The termination assembly type (simplex/duplex) determines the CIP messages
for corresponding CIP objects that the adapter processes for each I/O module.
Ethernet 1
Ethernet 2
Reset
Ethernet 1
Ethernet 2
Reset
Module A
Port 1
Port 2
Module B
Port 1
Port 2
Module Status
Redundancy Status
Network Status
Rack Status
Module Status
Redundancy Status
Network Status
Rack Status
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