ABB ACS880-1604, Hardware Manual

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24 Operation principle and hardware description
Hardware description

R8i and BDCL filter modules
The R8i DC/DC converter modules and BDCL filter modules run on wheels, and can easily
be removed from the cubicle for cable installation or service.
The quick connector at the back of the R8i module couples when the module is inserted
into the cubicle.
The control electronics of the R8i module need to be powered from an external auxiliary
voltage source. The R8i speed-controlled cooling fan (delivered as standard) is supplied
internally from DC. If a direct-on-line fan (C188) is used, the user must connect the
fan supply (400 V AC / 50 Hz / 60 Hz) to the module control connector [X50].
The control unit of the DC/DC converter controls the direct-on-line fan of the filter. The user
must connect the fan supply to the filter connector [X30]. For the connections, see
Filter
module connectors X30 and X55 on page 28 .
A single BCU control unit controls the R8i modules. The control unit is installed separately
from the module(s). A fiber optic link connects the control unit to each R8i converter
module. The control unit can be powered from a module connector [X53], from an external
24 V DC supply, or both for redundancy. The control unit contains the basic I/Os and slots
for optional I/O modules. For descriptions of the I/O terminals on the control unit, see
chapter
Control unit on page 161 and Fiber optic connectors of the DC/DC converter
module on page 77 .
See also the Installation examples in chapter Cabinet construction .

DC bus connection and capacitor charging
The converter unit must be equipped with DC fuses on the DC bus side and with output
DC fuses on the energy storage side. The user must equip also the energy storage with
fuses for protecting the energy storage cable in a cable short-circuit situation.
A DC switch/disconnector can be installed if quick isolation of the module from the DC bus
is required.
A capacitor charging circuit must be fitted if
•
the converter module is connected to the DC bus through a DC switch/disconnector,
or
•
the converter unit is directly connected to the DC bus and the supply unit of the system
does not have charging capability.
The charging circuit design presented in this manual consists of a charging switch [Q10.1],
resistors [R10.1] and a charging controller [A11.1]. When the converter unit is connected
to an energized DC bus, the charging switch is closed first. When the charging is finished,
the main DC switch/disconnector can be closed and the charging switch opened. (The
converter unit will not start if the charging switch is closed.)
See also the Installation examples in chapter Cabinet construction .