55
Instructional Leaflet
IB2C12063H03
Effective March 2012
Instructions for Installation, Operation and
Maintenance of Magnum SB Insulated Case
Low Voltage Power Circuit Breakers
EATON CORPORATION
www.eaton.com
Section 4: Drawout Circuit Breaker And
Cassette
General
Section 3 discussed topics and features common to all
Magnum SB circuit breakers, no matter what the mounting
configuration or type . In this section, features unique to
the drawout type circuit breaker and drawout cassette, not
covered elsewhere, are discussed . Drawings and dimensions
associated with all circuit breakers, drawout cassettes and
any appropriate primary bus connections can be found in a
separate document entitled Engineering Data TD01301004E .
The installation and levering of a drawout circuit breaker were
discussed in Section 2 . If necessary, review that information,
since it will not be repeated here .
Figure 80. Drawout Circuit Breaker in Cassette
Drawout Cassette
A drawout circuit breaker is used in combination with a fixed
drawout cassette (
Figures 80 and 82
) . The drawout circuit
breaker is equipped with automatic primary disconnects
(
Figure 81
) . The cassette provides all of the necessary
interfaces to the drawout circuit breaker including automatic
primary and secondary connections . For the narrow frame
circuit breaker a single cassette style using horizontal stabs
and horizontal customer bus bar terminals is available (
Figure
83
) . For the standard and double-wide circuit breakers three
cassette styles, all with vertical stabs, are available: basic,
standard, and universal . The standard cassette supplies vertical
stab/terminals only (
Figure 85
) . The basic cassette omits the
copper stab/terminals so that these pieces can be integrated
with vertical bus bars provided by the switchgear builder
(
Figure 84
) . The universal cassette provides a set of flat pad
terminals on the rear of the cassette that can be adapted to
vertical, horizontal or front connection (
Figures 86
) . Mounting
locations for cell (TOC) switches, safety shutters, mechanical
interlocks and key interlocks are provided on the cassette .
Figure 81. Drawout Circuit Breaker with Automatic Primary
Disconnects
