Square D QMB324W – 200A, 240V, 3-Pole Fusible Panelboard Switch – QMB Series

Meet the Square D QMB324W, a purpose-built 200 A, 240 V, 3‑pole fusible panelboard switch engineered for demanding commercial and light industrial environments. As part of Schneider Electric’s trusted QMB Series, this device delivers a clear, reliable load disconnect and robust overcurrent protection when paired with the correct fuse class, making it a dependable choice for modern panelboards.

Why the QMB324W stands out

• High fault current tolerance with a 200 kAIC interrupt rating, designed to safely interrupt substantial fault currents at 240 V without compromising downstream equipment.
• Three‑phase, balanced isolation via a 3‑pole design, ensuring uniform disconnection across all conductors and simplifying maintenance in three‑phase systems.
• Seamless QMB integration purpose-built to work with Square D QMB fusible panelboards, streamlining sourcing of accessories and ensuring consistent performance.
• Primary load disconnect and overcurrent protection that supports reliable protection for feeders feeding motor controls, lighting circuits, and processing equipment.
• Clear, straightforward maintenance with predictable disconnection points, reducing downtime and improving safety during lockout/tagout procedures.

Ideal use cases

• Primary load disconnect for three‑phase distribution panels in commercial facilities or light industrial settings.
• Feeder protection for motor control centers, conveyor lines, or processing equipment housed in QMB panelboards.
• Retrofit or modernization projects where a dependable fusible switch is required to meet safety and protection standards.

Key specifications at a glance

• Series: QMB
• Part Number: QMB324W
• Amperage: 200 A
• Voltage: 240 V
• Poles: 3 (3‑pole configuration)
• Interrupt Rating: 200 kAIC

Installation and compatibility guidance

For optimal performance, use the correct fuse class specified for QMB fusible panelboards. Ensure wiring, enclosure sizing, and mounting comply with applicable electrical codes and local requirements. The 3‑pole configuration is ideal for three‑phase feeders, delivering uniform isolation across all phases during service upgrades or panel modernization.

Practical tips for best results

• Plan synchronized disconnects across all three phases to minimize arc flash risks during maintenance.
• Keep a stock of compatible fuses on hand to minimize downtime during inspections or fault events.
• Document the exact fuse class used with the QMB324W for future service and compliance audits.

Choose the QMB324W for a proven, code‑compliant solution that combines high fault current capability with straightforward integration into Square D QMB fusible panelboards. It’s designed to deliver dependable protection for downstream loads while simplifying maintenance and upgrade workflows in commercial and light industrial applications.