ABB ACS880-07, Hardware Manual

Page: 84 / 274

Power cable types for limited use
Use as motor cabling Use as input power cabling Cable type
No Yes
„
„
PE
A four-conductor system: three
phase conductors and a PE conduct-
or on a cable tray
Only with phase conductor cross
section less than 10 mm
2 (8 AWG)
or motors < 30 kW (40 hp).
Yes
EMT
Corrugated cable with three phase
conductors and a PE conductor, or
cable in EMT conduit
Only with motors up to 100 kW if
there is potential equalization
between the frames of motor and
driven equipment. Yes
A well-shielded (Al/Cu shield) four-
conductor system (three phase
conductors and a PE conductor or
four conductors)
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 PE conductor, make sure that the conductivity agree
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.
84 Guidelines for planning the electrical installation