MKS Novx 5000 Series, User Manual

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19-5000-M Version 1 19 Voltage Detection System Series 5000
A human wearing shoes and walking over an insulated surface such as a
carpet is an example of charging by triboelectrification. Each time a shoe
sole separates from the carpet electrons will be extracted from one
material and gained by the other material.
Another example is that of an integrated circuit sliding down a conductive
plastic tube. As the IC slides down the tube, friction occurs between the
two materials. One of them will gain electrons, thus becoming negatively
charged.
8.1.2 Induction Charging
Induction Charging occurs when a neutral conducting body is brought into
the electric field of a charged body. Charge polarization will occur in the
conducting body.
While the conducting body is still under the influence of the electric field,
the conducting body is momentarily grounded--a neutralizing charge will
be drawn up from the earth to annihilate the charge polarization.
When the ground connection is removed and the conducting body is
physically moved away from the electric field of the charged body, the
conducting body will end up with a net charge which is opposite in polarity
to the charge of the charged body.
A practical example of induction charging is when a charged human body
walks in close proximity to a printed circuit board which happens to be
lying on an insulated surface such as a workbench. In addition, one of the
edges of the PCB happens to be very close (millimeters) away from a
grounded wire or another conducting structure.
As the charged human body walks past the PCB, charge polarization
occurs in the PCB and, if the electrical field is high enough, arcing occurs
between the edge of the PCB and the grounded wire. The arc being in fact
the “grounding connection” described earlier. As the human being walks
away from the PCB, the PCB will be left with a net charge which, in turn,
may cause a second discharge if this PCB is handled improperly
subsequently.