ABB ACQ580-34, Руководство по оборудованию

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Unless local wiring regulations state otherwise, the cross-sectional area of the protective
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 conductor can either 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 conductor related to
the phase conductor size according to IEC/UL 61800-5-1 when the phase conductor and
the protective conductor are made of the same metal. If this is not so, the cross-sectional
area of the protective grounding conductor shall be determined in a manner which produces
a conductance equivalent to that which results from the application of this table.
Minimum cross-sectional area of the corresponding
protective conductor
S
p
(mm
2
)
Cross-sectional area of the phase conductors
S (mm 2 )
S
1)
S ≤ 16
16 16 < S ≤ 35
S/2 35 < S
1) To comply with standard IEC/EN 61800-5-1 (UL 61800-5-1)
•use a protective earth conductor with a minimum cross-sectional area of 10 mm 2 Cu or 16 mm 2 Al (as an alternative
when aluminum cables are permitted),
or
•use a second protective earth conductor of the same cross-sectional area as the original protective earth conductor,
or
•use a device that automatically disconnects the supply if the protective earth conductor is damaged.
If the protective earth conductor is separate (that is, it does not form part of the input power cable or the input power cable
enclosure), the minimum cross-sectional area must be:
•2.5 mm
2
when the conductor is mechanically protected,
or
•4 mm 2 when the conductor is not mechanically protected.
￭
Typical power cable sizes
See the technical data.
￭
Power cable types
Preferred power cable types
This section presents the preferred cable types. Make sure that the selected cable type also
complies with local/state/country electrical codes.
Use as motor cabling Use as input power cabling Cable type
Yes Yes
„
„
PE
Symmetrical shielded (or armored)
cable with three phase conductors
and concentric PE conductor as
shield (or armor)
Guidelines for planning the electrical installation 79