Alternative Power Cable Types; Motor Cable Shield - ABB ACQ810-04 Hardware Manual

42 Planning the electrical installation

Alternative power cable types

Power cable types that can be used with the drive are represented below.
(also recommended for supply cabling)
Symmetrical shielded cable: three phase
conductors and a concentric or otherwise
symmetrically constructed PE conductor, and a
shield
PE conductor
and shield
Allowed for supply cabling
A four-conductor system: three phase
conductors and a protective conductor.

Motor cable shield

To function as a protective conductor, the shield must have the same cross-sectional
area as a phase conductor when they are made of the same metal.
To effectively suppress radiated and conducted radio-frequency emissions, the shield
conductivity must be at least 1/10 of the phase conductor conductivity. The
requirements are easily met with a copper or aluminium 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. The better and
tighter the shield, the lower the emission level and the bearing currents.
Insulation jacket
Motor cable
Shield
PE
Copper wire screen
Note: A separate PE conductor is required if
the conductivity of the cable shield is not
sufficient for the purpose. See section
rules above.
PE
Helix of copper tape
General
Shield
PE
Shield
PE
Inner insulation
Cable core