Westinghouse | MCA3400 | Circuit Breaker | 400A | 3-Pole | 600V

The Westinghouse MCA3400 circuit breaker is engineered for demanding 600V power distribution, delivering dependable protection for high-current circuits. With a robust 400A rating across 3 poles, this unit is designed to safeguard main feeders and critical loads in commercial and industrial panels without compromising on performance or reliability.

Designed for maintenance, retrofit, and replacement projects where exact specifications matter, the MCA3400 integrates smoothly with Westinghouse-compatible panels and systems that rely on this familiar MCA3400 family design. Its three-pole configuration ensures synchronized protection across all phases, helping to maintain system stability in demanding applications.

Key specifications

• Amperage: 400 A
• Poles: 3-Pole
• Voltage: 600 V
• Part number: MCA3400

Why this breaker stands out

What sets the MCA3400 apart is its clear emphasis on compatibility and practical field use. The part number MCA3400 is the most reliable reference when matching this breaker to existing panels or replacement stock, reducing the risk of mismatched ratings or mounting styles during retrofit or maintenance. This makes it a practical choice for facilities that require quick, accurate ordering and dependable interchangeability.

Ideal use cases

• Replacement in commercial or industrial panels that support 3-pole, 600V protection for main feeders
• Retrofit projects upgrading older electrical systems to a standardized 400A, 3-Pole configuration
• Maintenance scenarios where a reliable, field-ready 400A breaker is needed to minimize downtime

Fit, compatibility, and installation tips

Before ordering, confirm the panel’s fit and ratings align with 400A, 3-Pole, and 600V specifications. Since the MCA3400 is keyed to its part number, keeping the packaging or documentation handy greatly simplifies future maintenance or replacements. When installing, verify mounting style and busbar compatibility with existing equipment to ensure a seamless swap and stable electrical connections.

Ideal for facility managers, electrical contractors, and maintenance teams working in warehouses, manufacturing floors, data centers, and other high-power environments, the Westinghouse MCA3400 provides a clear path to reliable protection, straightforward replacement, and efficient upgrades. By choosing a trusted, compatible 400A, 3-pole 600V breaker, you safeguard uptime and maintain orderly, safe power distribution across demanding workloads.