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

System modifications during redundant operation
10.6 Re-parameterization of a module
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
I/O modules
1) Central modules are also reset first. 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.
10.6.6

Step 5: Transition to redundant system mode

Starting situation
The fault-tolerant system operates with the modified 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".
164
One-sided I/O of previous
master CPU
are no longer addressed by the
CPU.
Output modules output the
configured substitute or holding
values.
One-sided I/O of new master
CPU
are given new parameter
settings and updated by the
1)
CPU.
CPU 410-5H Process Automation/CPU 410 SMART
Switched I/O
continue operation without
interruption.
System Manual, 10/2013, A5E32631667-AA