Siemens SIMATIC CPU 410

Replacement of failed components during redundant operation
13.1 Replacement of central components
CPU 410 Process Automation/CPU 410 SMART
230 System Manual, 05/2017, A5E31622160-AC
Starting situation
Failure
How does the system react?
Simultaneous failure of both fiber-optic cables
The S7-400H is in the redundant system state
and
both
fiber-optic cables fail.
• Both CPUs report the event in the diagnostic
buffer and via OB 72.
• Both CPUs become master CPU and remain
in RUN.
• The LEDs IFM1F and IFM2F are lit on both
CPUs.
Procedure
The described double fault results in loss of redundancy and partial or complete failure of
switched DP or PN I/O. In this event proceed as follows:
Step
What to do?
How does the system react?
1 Switch off one subsystem. -
2
Replace the faulty components.
-
3 Turn the subsystem back on.
• LEDs IFM1F and IFMF2F go off. The
LED MSTR of the switched on subsys-
tem goes out.
4 Start the CPU.
• The CPU performs an automatic LINK-
UP and UPDATE.
• The CPU switches to RUN (redundant
system state) and operates as standby
CPU.