Use as motor cablingUse as input power cablingCable type
Yes with motors up to 100 kW
(135 hp). A potential equalization
between the frames of motor and
driven equipment is required.
Yes
Well-shielded (Al/Cu shield or ar-
mor) four-conductor cable (three
phase conductors and a PE)
NoYes
WARNING!
If you use unshielded high-
power input power cables
in an IT network, make sure
that the non-conductive
outer sheath (jacket) of the
cables have good contact
with a properly grounded
conductive surface, for ex-
ample, install the cables on
a properly grounded cable
tray. Otherwise voltage may
become present on the non-
conductive outer sheath of
the cables, and there is
even a risk of an electric
shock.
A single-core cable system: three
phase conductors and PE conductor
on cable tray
Preferable cable arrangement to
avoid voltage or current unbalance
between the phases
Not allowed power cable types
Use as motor cablingUse as input power cablingCable type
NoNo
Symmetrical shielded cable with in-
dividual shields for each phase
conductor
￭ Power cable shield
If the cable shield is used as the sole PE conductor, make sure that its conductivity agrees
with the PE conductor requirements.
To effectively suppress radiated and conducted radio-frequency emissions, the cable shield
conductivity must be at least 1/10 of the phase conductor conductivity. The requirements
are easily met with a copper or aluminum shield. The minimum requirement of the motor
cable shield of the drive is shown below. It consists of a concentric layer of copper wires
with an open helix of copper tape or copper wire. The better and tighter the shield, the lower
the emission level and bearing currents.
26 Electrical planning guidelines
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