ABB ACS880 Series, Руководство по планированию электроснабжения

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Use as motor cabling Use as input power cabling Cable 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)
No Yes
„
„
PE
WARNING!
If you use unshielded
single-core cables in an IT
network, make sure that the
non-conductive outer
sheath (jacket) of the cables
have good contact with a
properly grounded conduct-
ive surface. For example,
install the cables on a prop-
erly grounded cable tray.
Otherwise voltage may be-
come 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
L1
L3 L2
L2
L1 L3
L3
L2 L1
Preferable cable arrangement to
avoid voltage or current unbalance
between the phases
Not allowed power cable types
Use as motor cabling Use as input power cabling Cable type
No No
„
„
PE
Symmetrical shielded cable with in-
dividual shields for each phase
conductor
￭ Power cable shield
If the cable shield is used as the sole protective earth (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.
Electrical planning guidelines 25