Eaton KD3400F-KT3400T 400A 3-Pole 600 V Circuit Breaker

Power downtime isn’t an option in demanding facilities. The Eaton KD3400F-KT3400T 400A 3-Pole 600 V Circuit Breaker delivers reliable, high-current overcurrent protection for serious three-phase electrical systems. Engineered to interrupt fault currents swiftly and safely, this breaker protects feeders, motors, and downstream equipment from damage and unplanned outages.

Core specs at a glance

• Current rating: 400 A
• Poles: 3
• Voltage rating: 600 V
• Part number: KD3400F-KT3400T

Why the 3-Pole design matters

For three-phase networks, a 3-pole breaker ensures all three hot legs disconnect together. This coordinated shutoff minimizes arc energy and protects motors and equipment that rely on balanced phase protection. The KD3400F-KT3400T is built to perform in high-demand environments where uninterrupted three-phase operation is essential, helping prevent cascading faults and equipment damage.

Ideal use cases and industries

• Industrial facilities with large 3-phase feeders and motor loads
• Distribution panels and switchgear that require a robust 400 A protection device
• Motor control centers and large equipment rooms in manufacturing, food and beverage, water treatment, and HVAC applications
• Commercial and industrial installations where 600 V systems are standard

Key benefits in real-world operation

• Safer fault clearing for three-phase equipment, reducing the risk of motor windings and conductor damage
• Clear, decisive interruption that helps maintain system integrity during faults
• Compatibility with standard 600 V, 3-pole configurations used in Eaton-compatible panels and distribution setups
• Durable construction designed for the rigors of heavy-load environments, contributing to longer service life and fewer nuisance trips

Practical installation and compatibility tips

When planning a replacement or integration, verify that your panel or switchgear supports a 400 A, 3-pole, 600 V breaker in the KD3400F-KT3400T family. Ensure proper trip coordination with downstream protective devices to align with your protection philosophy. Confirm enclosure space, bus bar fitment, and mounting provisions match the breaker’s physical profile to ensure a straightforward, reliable installation.

Who should consider this breaker

Facilities managers, electrical engineers, and maintenance technicians dealing with high-current, three-phase electrical systems should consider the KD3400F-KT3400T when upgrading or stocking spare breakers for critical infrastructure. Its 400 A rating and 600 V capability address the protection needs of large motors, heavy feeders, and substantial distribution networks without compromising reliability.