Step 5: Transition To Redundant System Mode - Siemens SIMATIC PCS 7 CPU 410-5H System Manual

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".
Result
The reserve CPU links up and is updated. The fault-tolerant system is operating in redundant
system mode.
Note
Any set up access right is not canceled until you stop the SIMATIC Manager. You should
reset the access right once again to prevent unauthorized access. You reset the access right
in the SIMATIC Manager with the menu command PLC > Access Rights > Cancel.
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
If one of the monitored times exceeds the configured maximum, the update is canceled. The
fault-tolerant system remains in single mode with the previous master CPU and, assuming
certain conditions are met, attempts the link-up and update later. For additional information,
refer to section Time monitoring (Page 123).
Where the values for the monitoring times in the CPUs differ, the higher values always apply.
CPU 410-5H Process Automation
System Manual, 09/2014, A5E31622160-AB
One-sided I/O of the standby
CPU
are given new parameter set-
tings and updated by the
1)
CPU.
System modifications during redundant operation
One-sided I/O of the master
CPU
continue operation without interruption.
10.5 Editing CPU parameters
Switched I/O
179