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.
Insulation jacket1
Helix of copper tape or copper wire2
Copper wire shield3
Inner insulation4
Cable core5
Grounding requirements
This section gives general requirements for grounding the drive. When you plan
the grounding of the drive, obey all the applicable national and local regulations.
The conductivity of the protective earth conductor(s) must be sufficient.
Unless local wiring regulations state otherwise, the cross-sectional area of the
protective earth conductor must agree with the conditions that require automatic
disconnection of the supply required in 411.3.2 of IEC 60364-4-41:2005 and be
capable of withstanding the prospective fault current during the disconnection
time of the protective device. The cross-sectional area of the protective earth
conductor must be selected from the table below or calculated according to 543.1
of IEC 60364-5-54.
This table shows the minimum cross-sectional area of the protective earth
conductor related to the phase conductor size according to IEC/UL 61800-5-1
when the phase conductor(s) and the protective earth conductor are made of the
same metal. If this is not so, the cross-sectional area of the protective earth
72 Guidelines for planning the electrical installation
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