Square D QMJ365 - 400A, 600V, 3-Phase, Switch

The Square D QMJ365 is a rugged 3‑phase switch engineered for dependable on/off isolation and overcurrent protection in demanding industrial and commercial environments. With a robust 400A rating at 600V, this switch handles heavy motor loads and distributed power with confidence, helping you minimize downtime and maximize safety during maintenance and servicing.

• Model: QMJ365
• Amperage: 400A
• Voltage: 600V
• Phase: 3-Phase

Why the QMJ365 stands out

• Compact, maintainable fusible switch: Designed for quick field service and straightforward component replacement, reducing maintenance time and labor.
• Reliable motor disconnect and protection: Ideal for motor disconnects, panelboards, and branch circuit protection where space is at a premium but protection is non-negotiable.
• Rugged for harsh environments: Built to endure demanding industrial and commercial settings while delivering dependable isolation when it matters most.
• Clear isolation for safe maintenance: Provides trusted on/off control so technicians can work with confidence and eliminate guesswork during servicing.

Ideal applications

• Motor disconnects in manufacturing lines, pumps, and compressors
• Panelboards where a compact, maintainable protection device is required
• Branch circuit protection for centralized power distribution in industrial facilities

Real-world use cases

• In a high-demand production line, the QMJ365 offers a rapid, reliable way to isolate motors for maintenance without removing power from the broader system.
• In commercial facilities, it serves as a compact distribution point that protects three-phase loads while keeping wiring neatly organized and accessible for service teams.
• for HVAC or processing equipment, the QMJ365 provides dependable protection against overcurrent events that could damage expensive motors and drives.

Installation and practical considerations

• Ensure the system is configured to support a 600V, 3-phase supply with the QMJ365 as the point of protection and isolation.
• Plan for a compact footprint that fits your panelboard or disconnect enclosure while maintaining accessible maintenance clearances.
• Label the switch clearly and maintain a straightforward turn-off procedure to facilitate safe servicing and emergency isolation.