Siemens SIMATIC S7-400H - Changing the Rack Number of an H CPU; Parameter Assignment Tool; Specially Saved Parameters

Installation of a CPU 41x-H
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Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
Parameter Assignment Tool
You can set the individual CPU parameters using “Configuring Hardware” in
STEP 7.
Note
If you make changes to the existing settings of the following parameters, the
operating system carries out initializations like those during cold restart.
• Size of the process image of the inputs
• Size of the process image of the inputs
• Size of the local data
• Number of diagnostics buffer inputs
• Communication resources
These initializations are:
– Data blocks are initialized with the load values
– M, C, T, I, Q are deleted irrespective of the retentivity setting (0)
– DBs generated via SFC are deleted
– Hard-coded, dynamic connections are cleared down, as are
the unconfigured connections of the X/I blocks from the active
side of the connection
– All the priority classes start from the beginning again
Specially Saved Parameters
The following parameters are specially saved in an H CPU.
• The module rack number of an H CPU (0 or 1)
• The operating mode of an H CPU (single or redundant mode)
These parameters are not deleted when a memory reset is performed and you
cannot change them in HW Config. The following describes how these parameters
can be changed.
Changing the Rack Number of an H CPU
To change the rack number of an H CPU, carry out the following steps:
1. Change the rack number on the synchronization module
2. Perform a power on without backup.
3. Perform a manual memory reset.