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RFC 4072R
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PHOENIX CONTACT
110146_en_00
3.2
System behavior and redundancy status
The sections below provide information on the behavior of the redundant control system as
well as changing the redundancy status of the control system and the controllers.
Information on the redundancy status is shown on the touch screen display of the controller,
.
3.2.1
Ideal typical system behavior
shows the ideal typical system behavior of the redundant control system during
error-free startup of the controllers.
Figure 3
-
3
Ideal typical system behavior
First
Second
Sync
HotStandBy (HSBY)
No Sync
BACKUP-Controller
PRIMARY-Controller
Basic Sync
FollowUp Sync
Set redundancy type
No synchronization
Synchronization connec
-
tion is active
PLCnext application is
synchronized
Redundancy functionality
is active
Establish synchronization
connection
Download
PLCnext application
HSBY conditions are met
)