Siemens SIMATIC PC 670, Equipment Manual

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ESD Guidelines
Release 04/02
B-2
Panel PC 670 Computing Unit, Equipment Manual
B.1 What does ESD mean?
Definition
All electronic components are equipped with high-integrated modules or
components. Conditioned by their technology, these electronic components are
extremely sensitive to overvoltages and therefore to discharges of static
electricity.
These Electrostatically sensible components/assemblies are internationally known
under the abbreviation as ESD. At the same the internationally used denomination
ESD for electrostatic sensitive device is also used.
Electrostatic sensitive assemblies are identified by the following symbol:
!
Caution
Electrostatic sensitive devices can be destroyed by voltages which are far below
the limit of perception of human beings. These voltages occur when you touch a
component or the electrical connections of a assembly without being
electrostatically discharged. The damage which arises in a assembly as a result of
overvoltage cannot usually be detected immediately, but only becomes apparent
after a lengthy operating period.