ABB ACS880-204LC, Hardware Manual

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Main breaker / contactor
A main breaker or contactor is needed for the following reasons:
• If the LCL filter is connected to the AC input power supply while the IGBT supply module
is not modulating/active, there is a risk that the filter responds to disturbance frequencies
in a distorted AC input and starts resonating, which may cause permanent damage to
the IGBT supply module, LCL filter and equipment connected to the DC bus. If the IGBT
supply module is stopped, faulty or otherwise inactive, it cannot counteract the resonance
of the filter.
• The IGBT supply module and the LCL filter cannot prevent power flow from the AC input
to the DC bus and further to the ACS880-104LC inverter module(s). Even if the
modulation of the IGBT supply module is stopped, the anti-parallel diodes in it enable
power flow to the DC bus and to the inverter(s). In other words, merely stopping the
IGBT supply module does not stop the system.
• The IGBT supply module is not protected against excessive current drawn from the DC
bus. If the motoring power (power demanded from the DC bus) exceeds the supplying
capability of the IGBT supply module, it trips. If the current demand remains or increases,
the IGBT supply module is damaged.
See also Electrical planning instructions for ACS880 liquid-cooled multidrive cabinets and
modules [3AXD50000048634 (English)].
Installing the charging circuit
The cabinet builder must install and connect the charging circuit. For connections, see
chapter
Example circuit diagrams . Consult ABB for more information on the components
and wirings needed. Note that ACS880-204LC contains two separate charging circuits:
AC-DC charging circuit (line-up charging) and DC-DC charging circuit.
Activate and tune the charging function in the control program. For information on tuning
the parameters, see
ACS880 IGBT supply control program firmware manual
[3AUA0000131562 (English)].
Connecting the external power supply cable for the auxiliary
circuit
Connectors are described in chapter Operation principle and hardware description .
Electrical installation 109
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