Eaton KD3400K - 400 A, 600 V, 3-Pole Circuit Breaker | AmpState

The Eaton KD3400K is a 400A, 600V, 3-pole molded case circuit breaker designed for dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Built to integrate seamlessly with matching OEM panel systems, this MCCB delivers precise protection where space, reliability, and fast response matter most.

Why the KD3400K stands out

• Compact molded case design maximizes panel space and simplifies installation, letting you fit robust protection into tighter electrical environments without compromising performance.
• Thermal-magnetic trip unit provides stable, repeatable protection characteristics. The thermal element handles overloads smoothly, while the magnetic element delivers rapid, dependable response to short circuits—reducing the risk of damage to wiring and equipment.
• OEM-compatible compatibility is engineered to work with the corresponding manufacturer’s load centers and panelboards, ensuring a clean fit, predictable performance, and easier maintenance.
• Versatile application range suitable for residential, commercial, and light industrial settings, giving you a single, reliable solution across multiple projects.

Key specifications at a glance

• Manufacturer: Eaton
• Part Number: KD3400K
• Type: Thermal-magnetic molded case circuit breaker (MCCB)
• Amperage Rating: 400A
• Voltage Rating: 600V
• Poles: 3
• Application: Branch circuit overcurrent and short-circuit protection

Practical use cases

• Service and distribution panels in commercial facilities where space is at a premium but protection must not be compromised.
• Upgrading or replacing aging breakers in light industrial panel centers to improve protection accuracy and trip performance.
• New installations in residential or multi-residential buildings requiring a robust 3-pole solution for feeder circuits and essential equipment.
• Systems that demand consistency across multiple panels, thanks to OEM-aligned compatibility that helps maintain uniform protection characteristics.

What problems does it solve?

• Prevents damage from overcurrent and short circuits by providing fast, predictable tripping behavior.
• Maximizes usable panel space without sacrificing protective capabilities—beneficial when panel configuration is tight or has limited clearance.
• Reduces maintenance headaches with a reliable thermal-magnetic trip that remains consistent across electrical loads and environmental conditions.

Installation and compatibility tips

Ensure your panel or load center is designed to accommodate a 3-pole, 400A MCCB with a 600V rating. The KD3400K is engineered for seamless integration with matching Eaton OEM panels, delivering consistent electrical performance and straightforward field replacement when needed. Always follow electrical codes and manufacturer guidelines for torque, termination sizes, and enclosure suitability.

Why choose Eaton for circuit protection

Eaton has a long-standing reputation for durable, dependable protection solutions. The KD3400K combines a compact form factor with precise thermal-magnetic protection, reducing the risk of nuisance trips while maintaining strong protection for conductors and connected equipment. In environments ranging from home systems to light industrial facilities, this 3-pole MCCB offers a practical, future-ready choice that aligns with your existing panel ecosystem.

In summary

The Eaton KD3400K is a purpose-built 400A, 600V, 3-pole molded case circuit breaker that delivers reliable branch circuit and short-circuit protection in panelboards and load centers. With its space-saving design, stable thermal-magnetic trip unit, and OEM-compatible compatibility, it’s a smart, durable choice for residential, commercial, and light industrial applications. When you need dependable protection that fits your panel system and performs consistently under demanding conditions, the KD3400K stands ready to deliver.