Siemens CPU 410-5H Process Automation - Step 5: Transition to Redundant System Mode

System modifications during redundant operation
10.5 Editing CPU parameters
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 10/2013, A5E32631667-AA
159
Result
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.
Reaction of the I/O
Type of I/O
One-sided I/O of previous
master CPU
One-sided I/O of new master
CPU
Switched I/O
I/O modules
are no longer addressed by the
CPU.
Output modules output the
configured substitute or holding
values.
are given new parameter
settings
1)
and updated by the
CPU.
continue operation without
interruption.
1) Central modules are first reset. Output modules briefly output 0 during this time (instead of the configured substitute or
hold values).
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.
10.5.6
Step 5: Transition to redundant system mode
Starting situation
The fault-tolerant system operates with the modified CPU parameters in single mode.
Procedure
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".