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The aim safely and
reliably transmit the highest possible data volume the
shortest time.
Wherever electric current flows, electromagnetic fields
are generated, but these fields must not allowed to
influence even distort the inform ation that is
transmitted usually the form digital data packets.
22. For this
reason, the electromagnetic influence should reduced
or ideally eliminated altogether the source the
interference. For
example, shielded copper wires can used data need
to transm itted path that subject high
electromagnetic influence.
An established term this context “Electromagnetic
Compatibility (EMC)”.
To reduce the effects electromagnetic influence as
much possible, measures are also put place protect
the devices and installations that could disturbed, with
shielding one the most commonly used methods. Wherever high current flows or
high-frequency currents are present, high level of
electromagnetic influence can expected. However, the transmission
rate heavily decreases the length the ire is
increased.y
Light signals
As the complexity plants and systems steadily increases,
so does the task collecting and distributing various
types plant and process data. Here, “safely and reliably” means more
than just protecting the data against external access, as
it also means ensuring data integrity physical level
