Siemens SIMATIC S7-400H System Manual page 187

Procedure
Follow the steps below to replace a CPU:
Step
1
2
3
4
5
6
7
Starting situation for replacement of the load memory
Failure
The S7-400H is in redundant mode and a load
memory access error occurs.
Procedure
Follow the steps below to replace the load memory:
Step
1
2
3
S7-400H
System Manual, 09/2007, A5E00267695-03
13.2 Failure and replacement of components during operation
What needs to be done?
Turn off the power supply module.
Replace the CPU. Make sure the rack
number is set correctly on the CPU.
Insert the synchronization modules.
Plug in the fiber-optic cable connections of
the synchronization modules.
Switch the power supply module on again.
Perform a CPU memory reset on the
replaced CPU.
Start the replaced CPU (for example
STOP³RUN or Start using the PG).
What needs to be done?
Replace the memory card on the stopped
CPU.
Perform a memory reset on the CPU with the
replaced memory card.
Start the CPU.
Failure and replacement of components during operation
How does the system react?
The entire subsystem is switched off
•
(system operating in single mode).
–
–
–
CPU runs the self-tests and changes to
•
STOP.
–
CPU performs automatic LINK-UP and
•
UPDATE.
CPU changes to RUN and operates as
•
the standby CPU.
How does the system react?
The relevant CPU changes to STOP and
•
requests a memory reset.
Partner CPU switches to single mode.
•
How does the system react?
–
–
CPU performs automatic LINK-UP and
•
UPDATE.
CPU changes to RUN and operates as
•
the standby CPU.
187