System modifications during redundant operation
10.6 Re-parameterization of a module
CPU 410-5H Process Automation/CPU 410 SMART
164 System Manual, 10/2013, A5E32631667-AA
The reserve CPU links up, is updated and becomes the master. The previous master CPU
switches to STOP mode, the fault-tolerant system continues operating in single mode.
One-sided I/O of previous
master CPU
One-sided I/O of new master
CPU
I/O modules
are no longer addressed by the
CPU.
Output modules output the
c
onfigured substitute or holding
values.
are given new parameter
settings
1)
and updated by the
CPU.
continue operation without
interruption.
1) Central modules are also reset first. Output modules briefly output 0 during this time (instead of the configured substitute
Reaction to monitoring timeout
The update is canceled and no change of master takes place if one of the monitored times
exceeds the configured maximum. The fault-tolerant system remains in single mode with the
previous master CPU and, assuming certain conditions are met, attempts the master
changeover later. For additional information, refer to section Time monitoring (Page 110).
Where the values for the monitoring times in the CPUs differ, the higher values always apply.
Step 5: Transition to redundant system mode
Starting situation
The fault-tolerant system operates with the modified parameters in single mode.
1. In SIMATIC Manager, select a CPU of the fault-tolerant system, then select "PLC >
Operating Mode" from the menu.
2. From the "Operating Mode" dialog box, select the reserve CPU, then click "Warm
Restart".