ABB MNS-MCC, Инструкция по установке, эксплуатации и обслуживанию

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M N S - MCC
LO W VO LTAG E M OTO R CO N T R O L C EN T ER
Mechanical design
The basic mechanical design includes (Fig. 5):
• Frame:
Folded sheet metal C-profile used to
create the frame- work of the sections.
• Enclosure:
The metal sheets that are attached
to the frame, creating the complete section.
• Internal constructions:
The cubicles, units,
wireways and other components inside the MCC.
Sections are constructed from galvanized or
powder-coated steel.
Section arrangement
MCC vertical sections are composed of the
following three main compartments (Fig. 6):
• Bus bar compartment:
The compartment where
the main bus bar system is installed.
• Equipment compartment:
Composed of one or
more cubicles that house the installed units (e.g.
feeders, starters, etc.), the main functional
elements of the MCC. The Bus Bar and Cable
Compartment provide power to and from the
units in the Equipment Compartment.
• Cable compartment (or vertical wireway):
The
location of most power and control wiring
connected to units.
The bus bars compartment is separated from the
equipment compartment by the multi-function wall
and/or other additional barriers. It is separated
from the vertical wireway by metal sheets.
Bus bar compartments
The main horizontal bus bar is installed in the bus
bar compartment located at the rear of the MCC.
The main horizontal bus may be supplied in various
configurations depending on the current rating.
This main bus runs the width of each section. The
bus in each section is designed to allow splicing
with the bus of the adjacent sections to create a
continuous horizontal bus the length of the lineup.
The splice links are located on the right-hand side
of each section and are slid to the right to bridge to
the bus in the adjacent section.
The horizontal bus is isolated from the front
accessible areas but is not isolated phase-to-
phase. An insulated bus bar is available as an
option.
Horizontal bus bars
The horizontal bus bar runs A, B and C phases from
top to bottom of each vertical section in one or two
levels.
Single bus-bar systems are installed at the upper
level. Double bus-bar systems are installed at the
upper and lower level.
Depending on the current ratings, 2 or 4 (for
one set) or 8 (for two sets) of bars per phase
are installed. Only MCC sections with the same
horizontal bus configuration may be coupled
(or spliced) together.
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05 —
06
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05 Frame, enclosure and
inside constructions
—
06 MCC Standard
compartments
Top plate
Internal construction
Side plate
Back plate
Front doors
Frame
Equipment
Compartment
Cable Compartment
(Vertical Wireway)
Bus Bar Compartment