What Is Esd - Siemens simatic c7-621 Hardware Installation Manual

Guidelines for Handling Electrostatically Sensitive Devices (ESD)
B.1

What is ESD?

Definition
All electronic modules are equipped with large-scale integrated ICs or
components. Due to their design, these electronic elements are very sensitive
to overvoltages and thus to any electrostatic discharge.
These Electrostatic Sensitive Devicesare commonly referred to by the
abbreviation ESD.
Electrostatic sensitive devices are labeled with the following symbol:
Caution
!
Electrostatic sensitive devices are subject to voltages that are far below the
voltage values that can still be perceived by human beings. These voltages
are present if you touch a component or module without previously being
electrostatically discharged. In most cases, the damage caused by an
over-voltage is not immediately noticeable and results in total damage only
after a prolonged period of operation.
B-2
C7-621 / C7-621 AS-i Control Systems
C79000-G7076-C621-01