Eaton JM60400-3MW22 Molded Case Circuit Breaker

The Eaton JM60400-3MW22 is a high‑quality molded case circuit breaker (MCCB) designed for reliable protection in commercial and industrial power distribution systems. With a continuous current rating of 400 A and a voltage rating of 600 VAC, it is suitable for use as a main disconnect or feeder breaker in panelboards, switchboards, and motor control centers. The JM series breakers combine thermal‑magnetic trip technology with compact dimensions and optional accessories for versatile application.

Key Features

• Frame: JM, 3‑pole

• Current rating: 400 A (fixed thermal)

• Voltage: 600 VAC maximum, 50/60 Hz

• Interrupting capacity: 35 kA RMS symmetrical at 480 VAC (standard), 18 kA at 600 VAC

• Trip type: thermal‑magnetic (fixed thermal, adjustable magnetic)

• Magnetic trip adjustment: 5x to 10x of rated current (field adjustable via dial)

• Connection: I‑Line plug‑in (for Eaton panelboards) or bolt‑on lugs (optional)

• Terminals: suitable for copper or aluminum conductors up to 500 kcmil

• Accessories: auxiliary switches, alarm contacts, shunt trip, undervoltage release, motor operator

• Standards: UL489, CSA C22.2 No. 5, IEC 60947‑2

Technical Specifications

Protection Characteristics

The thermal‑magnetic trip unit provides two levels of protection: the thermal bimetal element responds to overload currents with an inverse‑time characteristic, allowing harmless inrush currents while tripping on sustained overloads. The magnetic solenoid reacts instantaneously to short‑circuit currents above the adjustable threshold, minimizing damage to downstream equipment. The trip mechanism is common to all poles, ensuring all phases are disconnected on a fault.

Applications

• Main breaker in lighting and distribution panelboards

• Feeder protection for commercial buildings and industrial plants

• Motor circuit protection (when used with separate overload relay)

• Transformer secondary protection

• Generator output breakers

Installation and Accessories

The JM60400-3MW22 with I‑Line connectors can be easily plugged into Eaton panelboards equipped with I‑Line bus stacks. For other applications, bolt‑on terminal kits are available. A wide range of field‑installable accessories includes internal auxiliary contacts for status indication, shunt trips for remote opening, and undervoltage releases for safety interlocks. The breaker can also be padlocked in the OFF position for lockout/tagout procedures.

With its robust construction and dependable protection, the Eaton JM60400-3MW22 is a trusted choice for electrical professionals requiring a high‑quality MCCB for critical power distribution.