ABB ACQ810-04, Hardware Manual, Page: 51 / 144

Planning the electrical installation 51

Alternative power cable types
The power cable types that can be used with the drive are represented below.

Motor cable shield
If the motor cable shield is used as the sole protective earth conductor of the motor,
ensure that the conductivity of the shield is sufficient. See subsection
General rules above,
or IEC 60439-1. 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 or copper wire. The
better and tighter the shield, the lower the emission level and bearing currents.
Recommended: Symmetrical shielded cable: three phase conductors and a concentric or
otherwise symmetrically constructed PE conductor, and a shield
PE conductor
and shield
Shield
Shield
Note: A separate PE conductor is
required if the conductivity of the
cable shield is < 50 % of the
conductivity of the phase
conductor.
PE
PE
Shield
PE
Not allowed for motor cabling : A four-conductor system (three phase conductors and a
protective conductor)
Not allowed for input or motor cabling: Symmetrical cable with individual shields for each phase
conductor
Shield
PE
Insulation jacket
Copper wire screen
Helix of copper tape
or copper wire
Cable core
Inner insulation