Failure and replacement of components during redundant operation
11.2 Failure and replacement of components of the distributed I/Os
CPU 410-5H Process Automation/CPU 410 SMART
176 System Manual, 10/2013, A5E32631667-AA
● PROFIBUS DP slave
● PROFIBUS DP cable
Note
Replacing I/O and function modules located in a distributed station is described in section
Fail
ure and replacement of an input/output or function module (Page 169).
Failure and replacement of a PROFIBUS DP master
Starting situation
How does the system react?
The S7-400H is in redundant system mode and a
DP master module fails.
• With single-channel one-sided I/O:
The DP master can no longer process
connected DP slaves.
• With switched I/O:
DP slaves are addressed via the DP master
Proceed as follows to replace a PROFIBUS DP master:
How does the system react?
1 Turn off the power supply of the central
The fault-tolerant system switches to single
2 Unplug the Profibus DP cable of the
affected DP master module.
–
Plug the Profibus DP back in.
5 Turn on the power supply of the central
rack.
• The CPU performs an automatic LINK-
UP and UPDATE.
•
The CPU changes to RUN and operates
as the reserve CPU.