Rockwell Automation 1785-BCM_BEM, D17856.5.4 PLC-5 Backup Communication Module User Manual - Manual (Page 150)

Reference Information
Appendix B
B-3
Q. How do I configure the remote I/O chassis in the PLC-5 backup
system?
A. Any valid remote I/O chassis configuration is acceptable. For more
information configuring remote I/O chassis, refer to the PLC-5
Enhanced and Ethernet Programmable Controllers User Manual
(publication 1785-6.5.12). PLC-5 Family Programmable Controllers
Installation Manual (publication 1785-6.6.1).
Q. What power supply should I use to supply power to the PLC-5
backup system?
A. In this manual, we use the 1771-P4S slot power supply as an example.
You, however, can use any of the power supplies listed in Chapter 3 to
supply power to your PLC-5 backup system.
Q. Should I use a separate power supply for each PLC-5 processor in
the backup system?
A. Yes, you should use a separate power supply for each processor to
avoid the loss of an entire system due to power failure. In addition,
you should connect the power supplies to different power sources to
take precautions against interruptions and incoming power failures.
Q. How do I terminate my Data Highway Plus and remote I/O links
in the PLC-5 backup system?
A. You should set each PLC-5 processor in the backup system as if the
other PLC-5 processor did not exist and no 1785-BCM modules are
present. For more information about terminating the Data Highway
Plus and remote I/O links, refer to the PLC-5 Enhanced and Ethernet
Programmable Controllers User Manual (publication 1785-6.5.12).
PLC-5 Family Programmable Controllers Installation Manual
(publication 1785-6.6.1).
Q. Should my PLC-5 processors have the same Data Highway Plus
station address?
A. Both PLC-5 processors must have the same Data Highway Plus station
address. To provide transparency to other stations on the DH+ link,
you set both stations to the same address. The 1785-BCM modules
permit only one of the two modules to be connected to the Data
Highway Plus at a time. In this configuration, remote PLC processors
and operator stations communicate to the processor that currently has
primary status.