Square D | MHF36400 | Circuit Breaker | 400A | 3-Pole | 600V

For demanding three‑phase electrical systems, the Square D MHF36400 Circuit Breaker provides dependable, code‑ready protection in a genuine Square D component. With a 400A rating, 3‑pole configuration, and a 600V rating, this breaker is engineered for maintenance, retrofit, and replacement projects where exact specifications matter and panel compatibility is critical. The MHF36400 is the precise reference you need to preserve system protection and warranty integrity.

• Amperage: 400 A
• Poles: 3‑Pole (three‑phase)
• Voltage rating: 600 V
• Part number: MHF36400
• Brand: Square D (Schneider Electric)

What makes it essential

In commercial and industrial distributions, a 400A three‑pole breaker protects feeders and downstream equipment across all three hot legs, ensuring coordinated tripping and minimizing damage from overloads or short circuits. The 600V rating expands its applicability to a wide range of power distribution scenarios while maintaining reliable performance under demanding load conditions.

Ideal use cases

• Retrofits: Replace aging protection with a matching Square D part to maintain panel compatibility and code compliance.
• Maintenance: Quick, field-ready replacement to restore circuit protection and reduce downtime in critical electrical rooms.
• New installations: Appropriate for main breaker positions in panels that require a 400A, 3‑pole, 600V protective device.

Compatibility and ordering guidance

Always confirm fit and ratings before ordering. Use the part number MHF36400 as your primary compatibility reference to ensure seamless integration with your Square D panel catalog and avoid mismatches in amperage, voltage, or pole configuration.

Practical tips for best results

• Follow local electrical codes and manufacturer installation guidelines to ensure safe, reliable operation.
• Coordinate with a licensed electrician when performing retrofit or replacement to verify panel compatibility and proper torqueing and enclosure fit.
• Keep a record of the exact part number (MHF36400) for future maintenance or procurement to simplify future replacements.