Grounding Requirements; Additional Grounding Requirements - Iec - ABB ACS880 Manual

32 Electrical planning guidelines

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 conductor must be
determined in a manner which produces a conductance equivalent to that which results
from the application of this table.
Cross-sectional area of the phase conductors
S (mm
16 < S ≤ 35
35 < S
1) For the minimum conductor size in IEC installations, refer to
If the protective earth conductor is not part of the input power cable or input power
cable enclosure, the minimum permitted cross-sectional area is:
2
• 2.5 mm if the conductor is mechanically protected,
or
2
• 4 mm if the conductor is not mechanically protected. If the equipment is
cord-connected, the protective earth conductor must be the last conductor to be
interrupted if there is a failure in the strain relief mechanism.
Additional grounding requirements – IEC
￭
This section gives grounding requirements according to standard IEC/EN 61800-5-1.
Because the normal touch current of the drive is more than 3.5 mA AC or 10 mA DC:
• the minimum size of the protective earth conductor must comply with the local
safety regulations for high protective earth conductor current equipment, and
• you must use one of these connection methods:
1. a fixed connection and:
• a protective earth conductor with a minimum cross-sectional area of
10 mm
permitted),
or
• a second protective earth conductor of the same cross-sectional area as
the original protective earth conductor,
2
)
S ≤ 16
2 2
Cu or 16 mm Al (as an alternative when aluminum cables are
Minimum cross-sectional area of the corresponding
protective earth conductor
S
p
Additional grounding requirements –
2
(mm )
1)
S
16
S/2
IEC.