Allen-Bradley 1732ES-IB12XOB4, User Manual, Page: 36 / 176

36 Rockwell Automation Publication 1791ES-UM001G-EN-P - November 2016
Chapter 2 About the Modules
A DLR network includes the following nodes.
Node Description
Supervisor node A DLR network requires at least one node to be configured as ring supervisor.
IMPORTANT: By default, the supervisor function is disabled on supervisor-capable devices, so they are ready to
participate in a linear/star network or as a ring node on a DLR network.
In a DLR network, you must configure at least one of the supervisor-capable devices as the ring supervisor before
physically connecting the ring. If you do not, the DLR network does not work.
The ring supervisor provides these main functions:
• Manages traffic on the DLR network
• Collects diagnostic information for the network
We recommend that you do the following:
• Configure at least one back-up supervisor.
• Configure the desired active ring supervisor with a numerically higher precedence value as compared to the back-up
supervisors.
• Track the supervisor-precedence values for all supervisor-enabled nodes in the DLR network.
Ring node A ring node is any node that operates on the network to process data that is transmitted over the network. A ring node
can also pass on the data to the next node on the network. When a fault occurs on the DLR network, the ring nodes
reconfigure themselves and relearn the network topology. Additionally, ring nodes can report fault locations to the active
ring supervisor.