Square D QMB326W – 600A, 240V, 3-Pole Fusible Panelboard Switch – QMB Series

The Square D QMB326W is a rugged 3-pole fusible panelboard switch engineered for dependable load disconnect and overcurrent protection in 3‑phase, 240V distribution systems. Rated for 600 A with a 200 kAIC interrupt capability, this device is designed to work with the appropriate fuse class to deliver precise protection where it matters most.

Why the QMB326W matters in real-world power systems

In three-phase layouts, fast, coordinated protection minimizes equipment damage and downtime. The QMB326W provides a clear, safe isolation point for maintenance or emergencies, enabling rapid fault clearance without invasive modifications to your QMB fusible panelboard. Its compatibility with standard fuse classes lets you tailor protection to your actual load profile, improving reliability and uptime across your electrical distribution.

Key capabilities that differentiate this unit

• 3-pole, 600 A, 240 V configuration delivers true three-phase protection for mid-size commercial and light industrial projects.
• 200 kAIC withstand rating supports high fault current environments, reducing the risk of nuisance trips and equipment damage.
• Designed as a main or sectional disconnect within QMB fusible panelboards, offering flexible protection structure.
• Part of the Schneider Electric Square D QMB Series, ensuring seamless integration with existing QMB panels and a consistent support ecosystem.
• Simple, straightforward protection where you need it most—at the point of interconnection and during maintenance access.

Ideal use cases

• Main disconnect for 3‑phase, 240V electrical panels in commercial facilities or light industrial environments.
• Sectional protection in distributed power systems where quick fault clearing and safe de-energization are critical.
• HVAC, manufacturing lines, or process equipment installations that require reliable overcurrent protection with easy maintenance access.

Compatibility, selection, and installation considerations

Before selecting this device, confirm it's paired with a QMB fusible panelboard and that the fuse class aligns with your protection strategy. Ensure your system operates at 240V in a three-phase configuration and that your site’s fault current warrants a 200 kAIC rating. Follow Schneider Electric installation guidelines for mounting, wiring, and fuse selection to maintain peak performance. Always isolate power and follow site-specific safety procedures during servicing, and keep spare fuse classes compatible with the QMB326W on hand for quick replacements.

What makes this a trustworthy choice

When you choose the Square D QMB326W, you’re selecting a proven fusible panelboard switch backed by Schneider Electric’s reliability and support. It’s purpose-built to provide a focused, dependable protection solution for 3‑phase 240V power distribution, with a clear path to safe maintenance and rapid fault clearance within QMB panel configurations.