Allen-Bradley CENTERLINE, Instruction Manual

Page: 9 / 88

1 Publication 2100-IN012B-EN-P—April 2005
Chapter
1
General Information
General Description
Allen-Bradley CENTERLINE ® Motor Control Centers (MCCs) consist of
one or more vertical sections containing electromagnetic and/or solid state
control devices that are prewired and tested within modular (plug-in) or frame
mounted (hard-wired) units.
CENTERLINE Motor Control Centers are designed in standard widths of
20” (508 mm), 25” (635 mm), 30” (762 mm), 35” (789 mm) and 40” (1016
mm). The standard front-mounted depths of an MCC are 15” (381 mm) and
20” (508 mm), in addition back-to-back mounted depths of 30” (762 mm) and
40” (1016 mm) are also offered. The standard height of an MCC is 90” (2286
mm). A 70.5” (1791 mm) high section is also available. All MCC sections are
supplied with top and bottom horizontal wireways. Most sections include
vertical wireways. Each 90” vertical section can accommodate up to 6.0 space
factors or 78” (1981 mm) for units.
Units (buckets) are designed in increments of 0.5 space factors. Each 0.5 space
factor is approximately 6.5” (165.1 mm) high. Units are designed as either
removable (plug-in) or frame-mounted (non-plug-in).
Individual units house a wide variety of power and logic devices. Plug-in units
are mounted on unit support pans within the section. Stab assemblies located
on the back of the unit plug onto the vertical bus. A mechanical interlock
prevents the unit door from being opened while the unit is energized. An
additional mechanical interlock prevents the unit from being plugged-in or
unplugged when the disconnect is closed.
Line power is distributed throughout the MCC via an isolated bus work
structure. The main horizontal bus is located in the center of each section.
Standard, center-fed, 300 ampere rated vertical bus supplies power to the
individual units above and below the horizontal bus for an effective 600
ampere capacity, allowing virtually unrestricted unit arrangement. An optional
600 ampere vertical bus provides 1200 ampere effective rating.