Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 - Manual (Page 27)

Installing a Backup System
Chapter 2
2-12
Figure 2.10
Backup Cable Wiring for Scanner Backup with Automatic Switchover
with Controllable Switchback (Cat. No. 1775ĆCBB)
1
3
2
4
5
6
1
3
2
4
5
6
1775ĆCBB
BACKUP CABLE
SCANNER #1
BACKUP
CONNECTOR
SCANNER #1
BACKUP
CONNECTOR
PRIMARY
PROCESSOR
BACKUP
PROCESSOR
SWITCH
SHIELD
10977ĆI
CAUTION: To guard against damage to equipment, make sure
that:
switch 2 closes within 8 milliseconds of switch 4
switch 3 closes within 8 milliseconds of switch 1
CAUTION: If these conditions are not satisfied when you
throw the switch to change the processor that is designated as
the primary processor to the processor currently controlling
outputs, the new primary processor may fault.