Products Description
Eaton IZMX40H3-V25W ACB Unit

Module Feature
IZMX40H3-V25W belongs to Eaton Moeller IZMX low voltage air circuit breaker family.
It is a withdrawable 3-pole breaker with 2500A frame current and H high breaking capacity grade. It is equipped with PXR20 trip unit which supports selective LSI protection, earth fault protection and local metering display. It adopts compact frame design, spring charging mechanism and mechanical/electrical interlock for racking operation safety. It supports optional motor charging, auxiliary contacts and communication module. It is widely used in industrial power plants, oil & gas stations and large commercial power centres for main distribution and bus section protection spare replacement.
Working principle
Built-in current transformers collect three-phase current signals and transmit data to the PXR20 trip unit.
When self-check detects overload, short-circuit or earth fault exceeding the preset threshold, the trip unit triggers the release mechanism to separate main contacts and cut off fault current. It stores fault parameters and alarm records locally, and uploads real-time measurement and diagnostic data to power monitoring system via communication module.
Onboard components
Silver alloy main contact assembly, arc extinguishing chamber, spring operating mechanism, CT set, PXR20 electronic trip unit, drawout carriage, racking interlock device, auxiliary contact block, status LED array, communication transceiver interface.
LED indicators
Front LEDs indicate power supply, spring charged status, trip alarm and communication link health.
Hardware self‑diagnosis
Continuous supervision detects trip unit power loss, CT circuit abnormality, internal over-temperature and communication interruption. Fault information and event logs can be checked on local display or Eaton Power Xpert software.
Programming software
Eaton Power Xpert Commissioning Tool, used for protection curve setting, metering configuration, communication parameter setup and fault record analysis.
Electrical & Process Parameters
Model:IZMX40H3-V25W Brand:Eaton Device type:Drawout air circuit breaker Rated current:2500A Icu:105kA @440V AC Function:Overload, short-circuit and earth fault protection for low voltage main incoming and bus tie circuits
Mechanical & Structure
Mounting:Switchgear withdrawable cassette installation Protection class:IP20 Housing:Metal insulated breaker enclosure
Environmental
Operating temperature:-25℃ ~ +70℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing
Certification:CE, IEC60947
Status:Original Eaton power distribution spare
Installation
Install the breaker in matched IZMX drawout cassette. Torque primary bus connection, test racking interlock, spring charging and protection trip function before energizing.
Interface
Primary power connection terminals, secondary control terminals, Ethernet communication port.
Diagnostic
Unexpected trip: Improper protection setting, CT wiring error or transient disturbance. Refusal to close: Discharged spring, missing control power or interlock locking. Communication offline: Damaged network cable or inconsistent network configuration.
Product Brief
Eaton IZMX40H3-V25W air circuit breaker, 2500A 105kA drawout ACB for industrial low voltage main switchgear maintenance replacement.