Rockwell Automation 2500 CENTERLINE Motor Control Centers Installation Manual - Manual (Page 95)

Rockwell Automation Publication 2500-IN001C-EN-P - April 2014 95
Glossary
The following terms and abbreviations are used throughout this manual.
For definitions of terms not listed here, refer to the Allen-Bradley Industrial
Automation Glossary, publication
AG-7.1 .
Column Vertical segment of a motor control center. Columns consist of the bus system,
units and wireways. Sometimes referred to as cubicle.
Conduit Metal tube that encloses electric wires and cables.
Connected position Plug-in unit operating position in which the line, load, control, network, and
protective earth (PE) connections are engaged. For more information, refer to
Chapter 6, Install and Remove Units .
Control station Door mounted assembly that houses push buttons, indicator lights and other
small control devices.
Control unit Unit that contains any type of power control or metering device including
starters, contactors, AC drives and soft starters.
Disconnected position Plug-in unit operating position in which line, load, control, network, and
protective earth (PE) connections are disengaged, but the unit is still housed in
the column. For more information, refer to
Chapter 6, Install and Remove Units .
Double-front Configuration in which columns are installed back-to-back. Columns with
double-front construction contain separate power bus systems that are spliced
together.
Feeder unit Unit containing a disconnection means used to distribute power to a remote
device.
Fixed unit Unit that is permanently mounted in a column. These units typically house
components that are large and/or require more current capacity than a plug-in
unit can provide. Sometimes referred to as a frame-mounted unit.
Locking mechanism Part of the withdraw lever. This mechanism must be engaged to select unit
operating positions. (See
Selecting an Operating Position on page 62 ).
Main switch Disconnecting means for a motor control center. Available in two types: circuit
breaker or disconnect switch.
Module space Grid size used to determine space distribution within the motor control center.
Height of one module is approximately 80 mm. Module width is 500 mm.
Motor control center (MCC) One or more columns operating with a common power bus.
Plating Type of surface treatment that distributes a layer of protective coating on
structural parts.