Siemens simatic c7-621, Руководство по установке оборудования

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B-3
C7-621 / C7-621 AS-i Control Systems
C79000-G7076-C621-01
B.2 Electrostatic Charging of Objects and Persons
Every object with no conductive connection to the electrical potential of its
surroundings can be charged electrostatically. In this way, voltages up to
15000 V can build up whereas minor changes, i.e. up to 100 V, are not
relevant.
Examples:
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Plastic covers up to 5 000 V
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Plastic cups up to 5 000 V
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Plastic-bound books and notebooks up to 8 000 V
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Desoldering device with plastic parts up to 8 000 V
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Walking on plastic flooring up to 12 000 V
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Sitting of a padded chair up to 15 000 V
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Walking on a carpet (synthetic) up to 15 000 V
An electrostatic discharge is
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Perceptible from 3500 V
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Audible from 4500 V,
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Visible from 5000 V
A fraction of these voltages is capable of destroying or damaging electronic
devices.
Carefully note and apply the protective measures described below to protect
and prolong the life of your modules and components.
Electrostatic
Charging
Limits for
Perceiving
Electrostatic
Discharges
Guidelines for Handling Electrostatically Sensitive Devices (ESD)