Eaton KDC3400W - 400 A, 600 V, 3-Pole Bolt-On Circuit Breaker | AmpState

The Eaton KDC3400W is a 400A, 600V, 3-pole bolt-on molded case circuit breaker designed to deliver reliable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Built for demanding electrical environments, this unit combines secure mechanical mounting with precise, repeatable protection to keep systems running smoothly.

What makes it stand out

• Secure bolt-on mounting ensures a rigid, vibration-resistant bus connection. This reduces movement during operation, improves contact stability, and minimizes arcing risk in installations with heavy loads or dynamic conditions.
• Thermal-magnetic trip unit delivers stable protection across a broad range of fault currents and temperatures. The thermal element handles overloads predictably, while the magnetic element provides instantaneous interruption for clear, short-circuit events.
• 3-pole design for 3-phase systems with a 400A rating, ideal for protecting multi-wire, 3-phase circuits in commercial and light-industrial environments.
• Compatibility is built in—designed to work with matching OEM load centers and panelboards, enabling straightforward substitutions and consistent performance across the system.
• Versatile protection suitable for residential, commercial, and light industrial applications, covering a wide range of distribution and feeder scenarios.

Technical specifications at a glance

• Manufacturer: Eaton
• Part Number: KDC3400W
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 400A
• Voltage Rating: 600V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Ideal use cases

• Protection for main feeders and branch circuits in large residential or multi-family panelboards.
• Commercial electrical distributions where reliable 3-phase protection is required for motors, compressors, and other heavy loads.
• Light industrial panels and distribution centers that experience vibration or thermal cycling, where a secure bolt-on connection improves long-term reliability.

Why choose this Eaton breaker over alternatives

• Its bolt-on mounting design minimizes connection loosening and movement, which translates to steadier protection under real-world conditions.
• The integrated thermal-magnetic trip provides coordinated protection without the need for additional accessories or adjustments, simplifying installation and maintenance.
• Compatibility with OEM panelboards ensures you can source a like-for-like replacement with confidence, preserving existing protection schemes and labeling.

Practical tips and insights

• Verify panelboard compatibility before replacement by matching the trip characteristics and enclosure style to existing equipment.
• When upgrading or replacing, consider the current and anticipated load profile to ensure the 400A rating aligns with feeder and downstream circuit requirements.
• In environments with frequent vibration (industrial equipment or large mechanical systems), rely on the bolt-on mounting to maintain a solid bus connection and consistent protection behavior.