Siemens SIMATIC S7-400H System Manual page 75

● Security levels
● Fault tolerance parameters
Parameter assignment tool
You can set the individual CPU parameters using "HW Config" in STEP 7.
Note
If you modify the parameters listed below, the operating system initializes the following:
 Size of the process input image
 Size of the process output image
 Size of the local data
 Number of diagnostic buffer entries
 Communication resources
This involves the following initialization actions:
 Data blocks are initialized with the load values
 Bit memories, timers, counters, inputs and outputs are deleted, regardless of their
 DBs generated by SFC will be deleted
 Permanently configured, basic communication connections are shut down
 All run levels are initialized.
Further settings
● The rack number of a fault-tolerant CPU, 0 or 1
● The operating mode of a fault-tolerant CPU: Stand-alone or redundant mode
S7-400H
System Manual, 03/2012, A5E00267695-11
Note
16 bit memory bytes and 8 counters are set by default in retentive memory, i.e., they are
not deleted at a CPU restart.
retentivity setting (0).
Use the selector switch on the rear panel of the CPU to change the rack number.
For information on how to change the operating mode of a fault-tolerant CPU, refer to
Appendix Stand-alone operation (Page 447).
5.10 Overview of the parameters for the S7-400H CPUs
Assembly of a CPU 41x–H
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