ABB ACS800 Series Hardware Manual page 61

Recommended
Symmetrical shielded cable: three phase conductors
and a concentric or otherwise symmetrically
constructed PE conductor, and a shield
PE conductor
and shield
A four conductor system:
three phase conductors
and a protective
conductor.
Shield
PE
PE
Can be used for rotor cables
(not recommended)
A separate PE conductor is required if the conductivity
of the cable shield is <50% of the conductivity of the
phase conductor.
Not allowed for rotor cables with phase
conductor cross section larger than 10 mm
(rotors > 30 kW).
Planning the electrical installation
Shield
PE
Shield
2
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