Additional resources – Rockwell Automation 1768-CNxxx ControlNet Communication Modules User Manual
Page 35
Rockwell Automation Publication CNET-IN005C-EN-P - July 2014
35
Redundant Media
Chapter 3
Additional Resources
For more information, see the ControlNet Standard and High-flex Coax Cable
Installation Instructions, publication
.
IMPORTANT
We recommend that you do not mix cable connections when using redundant
cabling, such as connecting trunk cable A to the B connector on the node.
Mixing cable connections makes it difficult to interpret cable fault indications
and locate a bad cable segment.
When in Redundant Cable mode, each node independently decides whether to
use channel A or channel B. This decision is based on error counters internal to
each node. Redundant cabling is only valid if there is only one fault on the
network. In other words, if you have a proper redundant cabling system and
you remove node 3 on trunk A and node 4 on trunk B, the system will not
operate correctly because a double failure has occurred.