Siemens simatic c7-621, Руководство по установке оборудования

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C7-621 / C7-621 AS-i Control Systems
C79000-G7076-C621-01
Safety of Electronic Controllers
The information in this section is of a general nature and applies to all types
of electronic controllers regardless of the manufacturer.
The reliability of SIMATIC devices and components is kept as high as
possible by comprehensive procedures during development and
manufacturing.
These include the following:
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The use of high-quality components
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The worst-case dimensioning of all circuits
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Systematic and computer-controlled testing of all externally supplied
components
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Burn-in of all large-scale integrated circuits (for example processors,
memory, etc.)
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Measures for preventing static charge when handling MOS circuits
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Visual checks at all levels of manufacture
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In-circuit test of all modules, in other words computer-supported testing
of all components and their interaction in the circuit
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Continuous tests at increased ambient temperatures over several days
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Thorough, computer-controlled final test
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Statistic evaluation of all returned products and immediate instigation of
corrective measures
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Monitoring of the most important control components with online tests
(parity monitoring in the RAM, watchdog for the CPU etc.).
These are basic measures that allow the vast majority of errors to be avoided
or detected.
Introduction
Reliability
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