INVT Goodrive300 Series User Manual

Goodrive300 Series VFD Peripherial options and parts
263
D.4 Cables
D.4.1 Power cables
Dimension the input power and motor cables according to local regulations.
• The input power and the motor cables must be able to carry the corresponding load currents.
• The cable must be rated for at least 70 °C maximum permissible temperature of the conductor
in continuous use.
• The conductivity of the PE conductor must be equal to that of the phase conductor (same
cross-sectional area).
• For details about the EMC requirements, see Appendix B "Technical data".
To meet the EMC requirements stipulated in the CE standards, you must use symmetrical shielded
cables as motor cables (as shown in the following figure).
Four-core cables can be used as input cables, but symmetrical shielded cables are recommended.
Compared with four-core cables, symmetrical shielded cables can reduce electromagnetic radiation
as well as the current and loss of the motor cables.
Shield
Jacket
Insulation
Conductor
PE
PE conductor and shield
Jacket
Insulation
Conductor
Jacket
Insulation
Conductor
PE
Symmetrical shielded cable
Four-conductor cable-
Note: If the conductivity of the shield layer of the motor cables cannot meet the requirements,
separate PE conductors must be used.
To protect the conductors, the cross-sectional area of the shielded cables must be the same as that of
the phase conductors if the cable and conductor are made of materials of the same type. This
reduces grounding resistance, and thus improves impedance continuity.
To effectively restrict the emission and conduction of radio frequency (RF) interference, the
conductivity of the shielded cable must at least be 1/10 of the conductivity of the phase conductor.
This requirement can be well met by a copper or aluminum shield layer. The following figure shows
the minimum requirement on motor cables of a VFD. The cable must consist of a layer of
spiral-shaped copper strips. The denser the shield layer is, the more effectively the electromagnetic
interference is restricted.
Cross-section of the cable
Insulation course
Wire screen

INVT Goodrive300 Series Specifications

General

Brand	INVT
Model	Goodrive300 Series
Category	DC Drives
Language	English