Teseq NSG 435, Руководство пользователя

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NSG 435 ESD simulator
2.1 Electrostatic discharge (ESD)
Under appropriate ambient conditions, both material objects and even the
human body itself can become charged with electrical energy. This effect is
due to «electrostatics», a phenomenon that has been known since the earliest
times. Thales von Milet (600 BC) noticed how amber attracted very light particles
when it was rubbed. Touching a charged item against a conductive object leads
to a charge equalization through a spark discharge which produces a brief but
powerful electromagnetic field.
This effect can be explained as follow: Two insulating substances with differing
dielectric constants become charged when rubbed together, i.e. one material
gives electrons to the other one. This effect is known as electrostatic charging.
The same can happen to a person. When somebody walks around in a dry
atmosphere on a carpet with good insulating properties, a charge of several
thousand volts can be built up. If, now, that person comes close to a conductive
surface, the charge that he or she is carrying flows away through a hefty spark
discharge.
The high equalizing current that flows, and the associated large electromagnetic
field that hence results, can cause electronic devices (computers, terminals,
process controllers, vehicle electronics, solid state devices, credit or memory
cards, etc.) to malfunction or even be destroyed.
2 INTRODUCTION