- 60 -
000868BG
5 - Installation
Grid output connection (AC side)
The inverter must be connected to a three-phase system with the center
of the star connected to ground. To connect the inverter to the grid is
possible to choose between the four-wire connection (3 phases + neutral)
and the three-wire connection (3 phases).
In any case, the inverter’s earth connection is mandatory.
The cable to be used can be ve-pole (four-wire conguration), or four-
pole (three-wire conguration).
Characteristics and sizing of the protective earth cable
ABB inverters must be earthed via the terminal with the protective earth
symbol and using a cable with an appropriate conductor cross-section
for the maximum ground fault current that the generating system might
experience. There are 2 earth connection point:
- Protective earth terminal (internal)
37
. It is positioned near to AC screw
terminal block inside the inverter mechanics.
- Protective earth terminal (external)
16
. It is positioned on the external
left side of the inverter mechanics.
Any failure of the inverter when it is not connected to earth through the appropriate terminal is
not covered by the warranty.
In compliance with standard IEC 62109 it is necessary:
• Install a earthing cable in one of the protective earth terminal with a
minimum section as indicated in the table below:
Cross-sectional area of phase
conductors (S)
(mm
2
)
Minimum cross-sectional
area of the protective earthing
conductor
(mm
2
)
S ≤ 16 S
16 < S ≤ 35 16
35 < S S/2
The value on this table are valid only if the protective earthing conductor is made of the
same metal as the phase conductors. If this is not so, the cross-sectional area of the earthing
conductor is to be determined in a manner which produces a conductance equivalent to that
which results from the application of this table.
• It is possible to install a second earthing cable (with the same section
as the rst one) positioning it in the protective earth terminal not used.
Installation of a second protective earth cable is also required by
regulations in force in certain countries of installation.
If necessary, carefully read the instructions provided in the paragraph "Installation of the
second protective earthing cable".