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Eaton / Westinghouse JKL3400 Molded Case Circuit Breaker

  • 400A
  • 3 Pole
  • Unit Mount
Eaton / Westinghouse JKL3400
Molded Case Circuit Breaker
Brand Eaton / Westinghouse
SKU JKL3400
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  • 400A
  • 3 Pole
  • Unit Mount

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Westinghouse JKL3400 3 Pole Circuit Breaker

Eaton / Westinghouse JKL3400 - 400A 3 Pole Molded Case Circuit Breaker

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$674.08 In Stock

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Description

Built to maintain older electrical infrastructure, the Eaton JKL3400 is a 3-pole, 400A molded case circuit breaker from the Series C J-Frame lineup. It integrates seamlessly into legacy Westinghouse and Cutler-Hammer motor control centers and panelboards without requiring modern adapters. Equipped with thermal-magnetic trip technology, this unit mount MCCB offers fixed thermal and adjustable magnetic protection, ensuring reliable performance with a 65kAIC rating at 240VAC.

Specifications

Key specifications
Brand Eaton / Westinghouse
Part Number JKL3400-R
Series JKL
Amperage 400A
Poles 3
Mounting Style Unit Mount
Voltage 600VAC, 250VDC
Phase 3
AIC Rating 65kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC
Fit and installation
Terminal Type Lugs
For Use With Westinghouse/Eaton Panelboards (e.g., PRL4), Switchboards, Motor Control Centers
Wire Gauge (1) 3/0 AWG - 500 kcmil (Al/Cu), (2) 3/0 AWG - 250 kcmil (Al/Cu)
Max Wire 500 kcmil
Min Wire 3/0 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Adjustable Magnetic
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch
Accessories Load Side Lugs
Standards CSA C22.2 No. 5, NEMA AB-1, UL 489
Approval CSA, UL
Temp Rating 40C
Construction Features High Interrupting Capacity

Product FAQs

5 answers
What equipment is the JKL3400 circuit breaker designed to fit?

This Series C J-Frame breaker is compatible with Eaton, Cutler-Hammer, and legacy Westinghouse distribution equipment, including PRL4 panelboards, switchboards, and motor control centers.

What are the wire size requirements for the JKL3400 lugs?

The factory-installed lugs can accommodate either a single conductor ranging from 3/0 AWG to 500 kcmil, or dual conductors from 3/0 AWG to 250 kcmil. The terminals are rated for both aluminum and copper wire.

How does the trip unit operate on the JKL3400?

It utilizes a thermal-magnetic trip unit that provides fixed thermal protection for long-time overloads and an adjustable magnetic setting. The adjustable magnetic dial allows electricians to customize the instantaneous short-circuit trip point based on specific load characteristics.

Will this breaker replace my older Westinghouse JKL3400?

Yes. Because Eaton acquired the Westinghouse electrical distribution line and Cutler-Hammer, the current Eaton JKL3400 is a direct drop-in replacement for legacy Westinghouse and Cutler-Hammer breakers sharing the same catalog number.

Does the JKL3400 require a specific mounting hardware kit?

As a unit-mount breaker, it bolts directly into the enclosure or onto the buswork. Depending on your specific panelboard or switchboard chassis, you may need to reuse your existing mounting hardware or source a separate strap kit if installing it into a new space.

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