Overview Of The Parameters For The S7-400 Cpus; Default Values; Parameter Blocks - Siemens SIMATIC S7-400H Manual

Installation of a CPU 41x-H
4.8

Overview of the Parameters for the S7-400 CPUs

Default Values

All the parameters have default settings at delivery. These defaults, which are
suitable for a whole range of standard applications, mean that the S7-400 can be
used immediately without the need for further settings.
You can find the CPU-specific default values using "Configuring Hardware" in
STEP 7.

Parameter Blocks

The activity and properties of the CPU are defined by parameters. The CPUs have
a defined default setting. You can change this default setting by modifying the
parameters.
The following list gives you an overview of the system properties available in the
CPUs that can be configured.
• General properties (e.g. MPI node no.)
• Startup (e.g. startup with POWER ON)
• Cycle/clock memory (e.g. cycle monitoring time)
• Retentivity (number of memory markers, timers and counters that are kept
retentive)
• Memory (e.g. local data)
Note: If, for example, you set greater or smaller values than the default values
for the process image, the number of diagnostics buffer entries and the
maximum number of ALARM-8 blocks and blocks for S7 communication, the
working memory available for the program code and for data blocks will be
reduced or increased by this amount.
• Assignment of interrupts (process interrupts, delay interrupts, asynchronous
error interrupts) to the priority classes
• Time-of-day interrupts (e.g. start, interval duration, priority)
• Watchdog interrupts (e.g. priority, interval duration)
• Diagnostics/clock (e.g. time synchronization)
• Protection levels
• H-specific parameters
Note
16 memory bytes and 8 counters are kept retentive in the default setting. In other
words, they are not deleted even when the CPU is rebooted.
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Automation System S7-400H Fault-tolerant Systems
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