Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 - Manual (Page 99)

Programming Techniques
Chapter 5
5-18
As long as the primary processor is controlling outputs, the station
address of the communication adapter module in the backup
processor is modified as shown in Table 5.C.
Table 5.C
Data Highway Station Numbers for 1775ĆKA Modules
If the station address is between:
The backup module assumes
a station address that is:
000
8
and 276
8
100
8
higher than the station address assigned to the
communication adapter module in the primary
processor.
300
8
and 376
8
200
8
lower than the station address assigned to the
communication adapter module in the primary
processor.
At switchover, the communication adapter module in the backup
processor assumes the station address assigned to it with the LIST
function.
5. Use the LIST function to enable the port used to connect the primary
processor to the backup processor, i.e., the Data Highway port or the
modem port.
1775ĆS5, ĆSR5 Modules
When configuring the Data Highway and Data Highway Plus channel
through LIST, you must make a backup selection. See Table 5.D.
Table 5.D
Data Highway Options
If backup is:
The Data Highway and Data Highway Plus station
number of the backup scanner module:
Selected will be automatically modified before and after switchover.
This allows you to have identical configurations in both the
primary and the backup processor.
Not Selected will remain the same both before and after switchover. The
primary and backup processors must have unique station
numbers.
Regardless of which mode you select, both the primary and the backup
Data Highway and Data Highway Plus channels are active. There is no
selection for the backup Data Highway or Data Highway Plus channel to
remain silent on the link until switchover.