Preface
Page 7 of 87
1.3.
ARCHITECTURE
The figure below provides an example of the typical network setup.
Figure 1.2. - Example of a typical network setup
By converting and redirecting serial DF1 messages from legacy devices to EtherNet/IP, the
module provides an interface for data exchange to ControlLogix and CompactLogix platforms.
When connected to devices that provide more than one DF1 port, it is possible to implement
DF1 communication redundancy with the use of two PLX51-DF1-ENI’s. These can be
configured in one of two modes, either Simultaneous or Active / Standby.
In the Simultaneous mode, both modules route the same traffic to the same Logix controller.
Effectively, the Logix controller will receive two of each message and process both of them.
Active / Standby mode requires both modes to be Logix “Owned”. One of the modules has its
routing capability disabled, achieved by setting the Inhibit Routing bit in the output assembly.
Logic in the Logix controller can monitor the connection and performance of the Active
module and, if necessary, inhibit the Active module and un-inhibit the Standby module.
