Step 7, Step Vi: Transition To Redundant State - Siemens SIMATIC S7-400H System Manual

14.6.6

STEP 7, step VI: Transition to redundant state

Starting situation
The fault-tolerant system is operating with the new (restricted) hardware configuration in
single mode.
Procedure
1. In SIMATIC Manager, select a CPU of the fault-tolerant system, then choose "PLC >
2. From the "Operating Mode" dialog box, select the standby CPU, then click "Warm Restart".
Result
The standby CPU links up and is updated. The fault-tolerant system is operating in
redundant mode.
Reaction of the I/O
Type of I/O
I/O modules to be
removed
1)
I/O modules still
present
DP stations to be
removed
No longer included in the hardware configuration, but still plugged in.
1)
Central modules are first reset. Output modules briefly output 0 during this time (instead of the configured substitute or
2)
hold values).
Reaction to monitoring timeout
If one of the monitored times exceeds the configured maximum the update is aborted. The
fault-tolerant system remains in single mode with the previous master CPU and, assuming
certain conditions are met, attempts to the link-up and update later. For further information,
refer to section Time monitoring (Page 106).
S7-400H
System Manual, 09/2007, A5E00267695-03
Operating Mode" from the menu.
One-sided I/O of standby CPU One-sided I/O of master CPU
are no longer addressed by the CPU.
are given new parameter
settings and updated by the
2)
CPU.
as for I/O modules to be removed (see above)
14.6 Removing components in STEP 7
continue operation without interruption.
System modifications in operation
Switched I/O
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