40
Operation and maintenance of
IZM low voltage air circuit breakers
MOELLER
www.moeller.net/de/support
10/09 AWB1230-1605
Effective October 2009
Section 4: Drawout circuit breaker
and cassette
General
Section 3 discussed topics and features common to all IZM circuit
breakers, no matter what the mounting configuration. In this section,
features unique to the drawout configuration not covered elsewhere,
including the drawout cassette, are covered. Drawings and
dimensions associated with all circuit breakers, drawout cassettes
and any appropriate primary bus connections can be found in a
separate document. 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.
Drawout cassette
A drawout circuit breaker is used in combination with a fixed
drawout cassette (
); the drawout circuit breaker is
equipped with automatic primary disconnects (
). The
cassette provides all of the necessary interfaces to the drawout
circuit breaker, including automatic primary and secondary
connections. For the IEC circuit breaker, a cassette style using
horizontal stabs and horizontal customer bus bar terminals is
available as standard (
). The cassette terminal connections
can be adapted to vertical bus bar connections with a variety of
optional vertical adapters.
Mounting locations for cell (TOC) switches, safety shutters,
mechanical interlocks, and key interlocks are provided on
the cassette.
Drawout circuit breaker dimensions
The IZM drawout circuit breaker connects to the fixed primary stabs
of the drawout cassette through the primary finger clusters attached
to the rear of the circuit breaker. Three different frame sizes cover all
IZM circuit breakers from an overall dimensional standpoint. Circuit
breaker drawings can be found in a separate document.
Drawout cassette dimensions
Cassette drawings provide all the dimensional information required
for all mounting configurations and can also be found in a separate
document. Review carefully for a specific installation.
Figure 62. Drawout Circuit Breaker in Cassette
Figure 63. Drawout Circuit Breaker with Automatic
Primary Disconnects
