Rockwell Automation 1786-RPFRXL ControlNet Fiber Ring Modules Installation Instructions - Manual (Page 10)

10 ControlNet Fiber-optic Ring Repeater Modules
Rockwell Automation Publication 1786-IN003D-EN-P - April 2011
Fiber-optic Ring Topology
Use this configuration for long distances. A fiber-optic ring may contain as many
as 20 member modules. These member modules (four shown in
Figure 2 )
include the following:
• 1786-RPA/B repeater adapter module
• 1786-RPFRL/B long-distance ring repeater module
• 1786-RPFRXL/B extra long-distance ring repeater module
Figure 2 - Fiber Ring Topology Example
TIP You cannot exceed 20 repeater modules in a series. If a ring is
broken, whether accidentally or on purpose for testing, the
configuration then becomes linear and the number of repeaters
depends on where the ring is broken. Most likely you will have as
many repeaters as in the original ring, such as the four shown in
Figure 2.
1786-RPA 1786-RPFR(X)L
1786-RPFR(X)L 1786-RPA
CH1 CH2
CH1 CH2
1786-RPA 1786-RPFR(X)L
1786-RPA 1786-RPFR(X)L
CH1 CH2
CH1 CH2
Rx Tx Rx Tx
Rx Tx Rx Tx
Rx Tx
Rx Tx Rx Tx
Rx Tx
1794-ACNR15
1794-ACNR15
1794-ACNR15
31237-M
On all fiber repeater modules, the leftmost connector is the RX (Receive) port;
the rightmost connector is the TX (Transmit) port.