ABB ACS880-87LC-3200A, Руководство по оборудованию

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Protecting the converter against ground faults in the converter or grid
cable
Both the grid-side converter and generator-side converter are equipped with an internal
ground fault protective function to protect them against ground faults in the converter itself
and grid cable. (This is not a personal safety or a fire protection feature.) You can disable
both ground fault protective functions (not recommended); refer to the firmware manual.
Implementing the emergency stop function
For further information, contact your local ABB representative.
Implementing the grid fault ride-through function
See the firmware manual.
Supplying power for the auxiliary circuits
The converter is equipped with an auxiliary voltage transformer.
In normal use, external auxiliary power supply is not needed. During start-up and maintenance
the converter auxiliary circuit can be supplied from the customer diesel generator. See
section
Connecting the external power supply cable for the auxiliary circuit (page 65) .
Using a safety switch between the converter and generator
To minimize the emission level when safety switches are installed in the generator cable
between the converter and the generator:
• Install the equipment in a metal enclosure in a way that the conduit or generator cable
shielding runs consistently without breaks from the converter to the generator.
Protecting the contacts of relay outputs
Inductive loads (such as relays, contactors and generators) cause voltage transients when
switched off.
The relay contacts of the control board are protected with varistors (250 V) against
overvoltage peaks. In spite of this, it is highly recommended to equip inductive loads with
noise attenuating circuits (varistors, RC filters [AC] or diodes [DC]) in order to minimize the
EMC emission at switch-off. If not suppressed, the disturbances may connect capacitively
or inductively to other conductors in the control cable and form a risk of malfunction in other
parts of the system.
Install the protective component as close to the inductive load as possible. Do not install
the protective components at the terminal block.
Planning the electrical installation 59