Failure And Replacement Of Profibus Dp Cables - Siemens CPU 410-5H Process Automation System Manual

Failure and replacement of components during redundant operation
11.2 Failure and replacement of components of the distributed I/Os
Step
3
4
11.2.4

Failure and replacement of PROFIBUS DP cables

Starting situation
Failure
The S7-400H is in redundant system mode and
the PROFIBUS DP cable is defective.
Replacement procedure
Proceed as follows to replace PROFIBUS DP cables:
Step
1
2
3
178
What has to be done?
Replace the IO device.
Plug the bus connector back in and turn the
power supply back on.
What has to be done?
Check the cabling and localize the
interrupted PROFIBUS DP cable.
Replace the defective cable.
Switch the failed modules to RUN
mode.
How does the system react?
–
The CPUs process the rack failure OB
•
86 synchronously (outgoing event)
The IO device can be addressed by the
•
respective DP master system.
How does the system react?
With single-channel one-sided I/O:
•
Rack failure OB (OB 86) is started (incoming
event). The DP master can no longer process
connected DP slaves
(station failure).
With switched I/O:
•
I/O redundancy error OB (OB 70) is started
(incoming event). DP slaves are addressed
via the DP master of the partner.
How does the system react?
–
–
The CPUs process the error OBs synchronized
with each other
With one-sided I/O:
•
Rack failure OB 86 (outgoing event)
The DP slaves can be addressed via the
DP master system.
With switched I/O:
•
I/O redundancy error OB 70 (outgoing
event).
The DP slaves can be addressed via both
DP master systems.
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 10/2013, A5E32631667-AA