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Eaton / Cutler-Hammer KS320300D Molded Case Circuit Breaker

  • 300A
  • 3 Pole
  • Unit Mount
Eaton / Cutler-Hammer KS320300D
Molded Case Circuit Breaker
Brand Eaton / Cutler-Hammer
SKU KS320300D
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  • 300A
  • 3 Pole
  • Unit Mount

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Eaton/Cutler-Hammer KS320300D 3 Pole Circuit Breaker

Eaton / Cutler-Hammer KS320300D - 300A 3 Pole Molded Case Circuit Breaker

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$950.16 No Stock

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Description

Part of the Eaton Series C family, the KS320300D is a K-frame, 3-pole, 300-amp molded case circuit breaker designed for commercial and industrial power distribution. It provides robust long-time and instantaneous (LI) protection for demanding electrical systems. This unit mount breaker installs into Eaton Series C panelboards, switchboards, and motor control centers. Rated at 65 kAIC at 240VAC, it features a non-interchangeable thermal-magnetic trip unit and includes line and load lugs.

Specifications

Key specifications
Brand Eaton / Cutler-Hammer
Part Number KS320300D
Series KS
Amperage 300A
Poles 3
Mounting Style Unit Mount
Voltage 240VAC
Phase 3
AIC Rating 65kA @ 240VAC
Fit and installation
Terminal Type Lugs
For Use With Eaton Series C Panelboards, Switchboards, Motor Control Centers
Wire Gauge 250-500 kcmil
Max Wire 500 kcmil
Min Wire 250 kcmil
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 Line and Load Lugs Included
Standards CSA C22.2 No. 5, NEMA AB 1, UL 489
Approval CSA, UL
Temp Rating 40C
Construction Features HACR Rated, Non-Interchangeable Trip

Product FAQs

4 answers
Can the KS320300D replace older Westinghouse K-frame breakers?

Yes, Eaton Series C K-frame breakers are the direct manufacturer-supported replacements for obsolete Westinghouse and Cutler-Hammer K-frame models, such as the KA, KB, or KD series. When installing in vintage CDP panelboards, a specific retrofit mounting kit may be required to adapt the bus connections.

Which panelboards accept the KS320300D circuit breaker?

This K-frame breaker is designed to mount in Eaton Series C panelboards, switchboards, and motor control centers. It is a unit-mount breaker, meaning it bolts directly to the chassis or mounting pan rather than plugging onto a busbar.

How is the short-circuit protection adjusted on the KS320300D?

This breaker features a thermal-magnetic trip unit with an adjustable magnetic setting. You can modify the instantaneous short-circuit trip threshold using the adjustment dial located directly on the front of the breaker to suit your specific load characteristics.

What does the LI trip function code mean on this breaker?

The LI designation indicates that the thermal-magnetic trip unit provides Long-Time (L) protection for continuous overloads and Instantaneous (I) protection for short circuits. The thermal element is fixed, while the magnetic element is adjustable.

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