Westinghouse | MCG3400 | Circuit Breaker | 400A | 3-Pole

Meet the Westinghouse MCG3400 Circuit Breaker — a rugged 400A, 3-Pole protection solution built for commercial and industrial electrical panels. Designed with maintenance, retrofit, and replacement projects in mind, this unit helps you restore reliable power protection quickly when your system is under load or aging equipment needs an upgrade.

Key specs at a glance: Amperage 400A, Poles 3-Pole, Part Number MCG3400. Using the exact part number is the most dependable way to verify compatibility with your Westinghouse panel or distribution setup.

Why this MCG3400 matters for your system

For three-phase distribution, a 3-Pole circuit breaker provides balanced protection across all phases, helping to prevent overheating and electrical faults from propagating through the circuit. The 400A rating makes it suitable for higher-load feeders and equipment that require robust circuit protection without frequent trip interruptions. This breaker is especially practical for retrofit projects where you’re updating older installations or replacing a failed unit without major panel changes, keeping downtime to a minimum and preserving existing wiring and labeling where possible.

Practical use cases include servicing commercial facilities, light-industrial environments, and large equipment rooms where dependable short-circuit protection and predictable trip behavior are essential. By choosing the MCG3400, you’re aligning with a trusted Westinghouse form factor that supports straightforward replacement in compatible panels and minimizes compatibility risk during maintenance cycles.

Before you order, confirm fit and ratings to avoid compatibility issues: verify that your panel is designed for 400A, that a 3-Pole configuration is appropriate for the circuit you’re protecting, and that the panel labeling references the MCG3400 or equivalent form factor. The part number is the best reference for compatibility and ensuring you receive the correct trip characteristics and mechanical fit—the foundation for safe, reliable operation.