Planning the electrical installation 49
Selecting the power cables
General rules
Select 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. For rated currents, see Drive specifications on page 319.
• The cable must be rated for at least 70
°C (158 °F) maximum permissible
temperature of conductor in continuous use. For the US, see Additional US
requirements on page 52.
• The conductivity of the PE conductor must be sufficient, see the table on page 49.
• A 600 V AC cable is accepted for up to 500 V AC.
To comply with the EMC requirements of the CE mark, use an approved cable type in
Recommended power cable types on page 51.
Use symmetrical shielded cable to reduce the following properties:
• electromagnetic emission of the drive system
• stress on motor insulation
• bearing currents
• general drive wear.
Sufficient conductivity of the protective conductor
The protective conductor must always have an adequate conductivity. The table
below shows the minimum cross-sectional area related to the phase conductor size
according to IEC 61439-1 when the phase conductor and the protective conductor
are made of the same metal.
Note: See the IEC/EN 61800-5-1 requirement on grounding (page 17).
Cross-sectional area of the phase
conductors S (mm
2
)
Minimum cross-sectional area of the
corresponding protective conductor S
p
(mm
2
)
S <
16 S
16 < S <
35 16
35 < S S/2