Grid Connection; Disconnecting Device (Disconnecting Means); Thermal Overload And Short Circuit Protection; Protection Against Short Circuit In Stator Cable - ABB ACS800 Series Hardware Manual

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Grid connection

Disconnecting device (disconnecting means)

The converter must be equipped with a hand operated input disconnecting device
(disconnecting means) which isolates the converter and the generator from the
supply grid. A switch fuse disconnector is available as option.
The disconnecting device does not, however, isolate the input busbars from the
supply grid. Therefore during installation and maintenance work on the converter,
the input cables and busbars must be isolated from the supply with a disconnector at
the distribution board or at the supplying transformer.
EU
To meet the European Union Directives, according to standard EN 60204-1, Safety
of Machinery, the disconnecting device must be one of the following types:
• a switch disconnector of utilization category AC-23B (EN 60947-3)
• a disconnector that has an auxiliary contact that in all cases causes switching
devices to break the load circuit before the opening of the main contacts of the
disconnector (EN 60947-3)
• a circuit breaker suitable for isolation in accordance with EN 60947-2.

Thermal overload and short circuit protection

Protection against short circuit in stator cable

The converter protects the generator stator cable and the generator in a short circuit
situation when the generator stator cable is dimensioned according to the nominal
current of the converter. No additional protection devices are needed.

Protection against short circuit inside the power cabinet

There are no additional short circuit protection devices besides the air breaker in
stator circuit and the disconnectors in line converter and auxiliary supply circuits.
There shall be a disconnector before the supplying transformer that meets the
requirement stated in the chapter

Protection against short circuit in generator rotor cable

The converter protects the generator rotor cable in a short circuit situation when the
generator rotor cable is dimensioned according to the nominal current of the
converter. No additional protection devices are needed.

Protection against short circuit inside the cabinet

Equip the converter with main fuses listed in chapter
restrict converter damage and prevent damage to adjoining equipment in case of a
short circuit inside the converter. Check that the operating time of the fuse is
below 0.5 seconds. The operating time depends on the fuse type (gG or aR),
supply network impedance and the cross-sectional area, material and length of the
Planning the electrical installation
Grid connection above.
Technical data. The fuses