Failure and replacement of components during redundant operation
11.1 Failure and replacement of central components
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 10/2013, A5E32631667-AA
173
How does the system react?
Failure of a fiber-optic cable or synchronization
module:
The S7-400H is in redundant system mode and a
fiber-optic cable or synchronization module fails.
See also chapter Synchronization modules for
the CPU 410-5H (Page 181).
• The master CPU reports the event in the
diagnostic buffer and with OB 72 of OB 82.
• The reserve CPU changes to ERROR-
SEARCH mode for some minutes. If the error
is eliminated during this time, the reserve
CPU switches to redundant system mode,
otherwise it switches to STOP.
• The LED Link1 OK or Link2 OK on the
synchronization module is lit.
Follow the steps below to replace a synchronization module or fiber-optic cable:
How does the system react?
First, check the fiber-optic cable.
2 Start the reserve CPU (for example, STOP-
RUN or Start using the programming device).
The following responses are possible:
1. CPU changes to RUN mode.
2. CPU changes to STOP mode. In this
case continue at step 3.
3 Remove the faulty synchronization module
–
4 Insert the new synchronization module in the
–
5 Plug in the fiber-optic cable connections of
the synchronization modules.
• The LED Link1 OK or Link2 OK on the
synchronization module goes out.
• Both CPUs report the event in the
diagnostic buffer
6 Start the reserve CPU (for example, STOP-
RUN or Start using the programming device).
The following responses are possible:
1. CPU changes to RUN mode.
2. CPU changes to STOP mode. In this
case continue at step 7.
7 If the reserve CPU changed to STOP in step
6:
Remove the synchronization module from the
master CPU.
• The master CPU processes swapping
interrupt OB 83 and redundancy error
OB 72 (entering state).
8 Insert the new synchronization module into
the master CPU.
• The master CPU processes swapping
interrupt OB 83 and redundancy error
OB 72 (exiting state).