Goodrive300-LIFT series inverter
Peripheral optional parts
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•
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).
•
Refer to chapter
Technical data
for the EMC requirements.
A symmetrical shielded motor cable (see the figure below) must be used to meet the EMC
requirements of the CE.
A four-conductor system is allowed for input cabling, but a shielded symmetrical cable is
recommended. Compared to a four-conductor system, the use of a symmetrical shielded cable
reduces electromagnetic emission of the whole drive system as well as motor bearing currents and
wear.
Shield layer
Jacket
Insulator
Conductor
PE
PE conductor and
shield layer
Jacket
Insulator
Conductor
Jacket
Insulator
Conductor
PE
Symmetrical shielded cable
Four-core cable
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Note
: A separate PE conductor is required if the conductivity of the cable shield is not sufficient for the
purpose.
To function as a protective conductor, the shield must have the same cross-sectional area as the
phase conductors 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 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. The better and tighter the shield, the lower the
emission level and bearing currents.
Cross-section of the cable
Insulating layer
Shield layer
D.4.2 Control cables
All analog control cables and the cable used for the frequency input must be shielded. Use a
double-shielded twisted pair cable (Figure a) for analog signals. Employ one individually shielded pair
for each signal. Do not use common return for different analog signals.
