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New generation IZM97, 99 low voltage air circuit breaker instruction manual
MN013010EN February 2020 www.eaton.com.cn
Section 1: Introduction
Section 1: Introduction
1-1 General information
The IZM9 air circuit breaker is a fixed or drawout air cir-
cuit breaker design using an electronic tripping system.
It is designed and tested for use at nominal voltages of
AC380/415V, 440V and 500/690V. IZM9 circuit breakers are
available in two physical frame sizes with continuous current
ratings from 800 to 6300A. The two physical frame sizes
have common height and depth dimensions, differing only
in width (Figure 1-1). The circuit breaker nameplate provides
complete rating information. All IZM9 circuit breakers are
100% rated, and are built and tested in an ISOT 9002 certi-
fied facility to applicable IEC and BS standards (Figure 1-2).
IZM9 circuit breakers use a rigid frame housing of engi-
neered thermoset composite resins, which has high-strength
structural properties, excellent dielectric characteristics, and
arc-tracking resistance.
The drawout IZM9 circuit breaker is a through-the-door
design having three breaker positions with the compartment
door closed (CONNECT, TEST, DISCONNECT) and one posi-
tion out of its compartment on extension rails (REMOVE).
The operating mechanism is a two-step stored energy mech-
anism, either manually or electrically operated.
When withdrawn on captive compartment cassette exten-
sion rails, IZM9 circuit breakers can be inspected, accessory
items added, and minor maintenance performed. The inside
of the compartment can also be inspected with the circuit
breaker on its extension rails.
NOTICE
Please read and understand these instructions before
attempting to unpack, install, operate, or maintain this equip-
ment. Study the breaker and its mechanism carefully before
attempting to operate it on an energized circuit.
WARNING
IZM9 circuit breakers should not under any circumstanc-
es be applied outside their nameplate ratings. Operation
outside of these ratings could result in death, bodily
injury, or property damage.
IZM97
IZM99
Figure 1-1 IZM97,99 low voltage circuit breakers (800-6300A)
