Teseq NSG 435, Руководство пользователя

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2.2 Simulation
A systematic investigation of electronic equipment and installations to deter-
mine their electromagnetic compatibility (EMC) is, today, a necessity if one is
not prepared to suffer the economic disadvantages that could otherwise ensue.
As a logical consequence, appropriate testing is now a legal requirement for
the sale of electronic products within the EC.
The ESD test plays an important role in the range of interference sensitivity
tests. It simulates frequently occurring effects and guides the development
engineer to any weak spots in an instrument or item of equipment through a
combination of high voltage and high frequency properties.
A simulation device must be constructed so that it reproduces practical con-
ditions realistically. Furthermore, the results obtained (interference sensitivity
threshold) must be reproducible.
The interference immunity of an instrument is not only dependent on its con-
struction, it is also largely dependent on the quality or the consistency of the
mass production techniques used. Knowing this has led to the demand for
individual testing or at least random sample testing.
Further weak spots, which could affect the overall interference immunity, can
arise through the assembly of instruments into complete systems because
of the installation method used, the cabling and the earthing. An ESD check
on systems is therefore also prescribed. Such tests provide valuable informa-
tion about the immunity of the system to effects that occur only sporadically
under operating conditions and hence represent difficult to detect sources of
disruption.