Siemens SIMATIC 627B, Operating Instructions Manual

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SIMATIC Box PC 627B
Operating Instructions, 06/2008, A5E00927393-02
219
ESD directives
B
B.1 ESD directives
Definition of ESD
All electronic modules are equipped with large-scale integrated ICs or components. Due to
their design, these electronic elements are highly sensitive to overvoltage, and thus to any
electrostatic discharge.
The electrostatic sensitive components/modules are commonly referred to as ESD devices.
This is also the international abbreviation for such devices.
ESD modules are identified by the following symbol:
CAUTION
ESD devices can be destroyed by voltages well below the threshold of human perception.
These static voltages develop when you touch a component or electrical connection of a
device without having drained the static charges present on your body. The electrostatic
discharge current may lead to latent failure of a module, that is, this damage may not be
significant immediately, but in operation may cause malfunction.