Hirschmann OZD Genius G12-1300, User Manual

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Installation OZD Profi 12M ...
Release 01 07/2017
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Potential equalization and screening
Figure 5: Laying cables inside of buildings
The cable screen should be connected to ground at both ends of the
cable. The use of fiber optic cable is recommended if problems are
experienced with interference. A low impedance potential equalization
cable should be used if this is not possible. Situations where interference
can present a problem include: plant which extends over a large area,
power is fed to the plant from different power sources, networking extends
over several buildings. If one of these situation apply, the following should
be observed when installing the potential equalization system:
 The circuit through which interference signals flow must be closed.
 Each part of the plant must be electrically connected to the potential
equalization system/functional ground at as many places as possible.
Electrically conducting pipes, parts of machines or supporting
structures should be integrated in the potential equalization system. In
order to ensure long-term reliability, appropriate measures should be
undertaken to protect against corrosion.

The potential equalization cable must be protected against corrosion.
 The cross-section of the potential equalization cable should be chosen
with regard to the maximum potential equalization currents which can
flow.
Special care should be taken when installing potential equalization cables
to maximize the interference immunity of the data cables. If possible, the
potential equalization cable should be laid parallel to and as close as
possible to the data cable (preferably in the same plastic pipe). The cable
screen should never be used for potential equalization. The potential
equalization cable should be finely stranded to ensure that it is also
effective at high frequencies as a result of the large surface area.
Bus cable
Potential equalization
Potential equalization
Control cabinet 1
Control cabinet 2