Square D QMB3640 - 400A, 600V, 3-Pole Panelboard Switch / Switchboard Unit | AmpState

Meet the Square D QMB3640 non-fusible panelboard switch — a purpose-built solution from Schneider Electric / Square D designed to power lighting and distribution panelboards with confidence. In a robust 3-pole configuration, this unit handles 400 A at 600 V, making it a practical choice for mid- to high-current, three-phase installations where reliability is non-negotiable.

Why this panelboard switch stands out

• Non-fusible design tailored for panelboard environments, delivering dependable load switching in three-phase systems without embedded fuse links.
• Three-pole configuration aligns with common 3-phase architectures used in commercial and industrial settings, providing straightforward integration with existing electrical layouts.
• Upstream protection compatibility engineered to work with standard upstream protection devices and fuse classes, helping you maintain proper protection coordination.
• Ready-to-install QMB family unit designed for seamless integration into current panelboards, reducing installation time and minimizing mounting adjustments.
• Versatile applications ideal for upgrading lighting and distribution panelboards in offices, factories, and large facilities where high-current switching and coordinated protection matter.

Specifications at a glance

• Amperage: 400 A
• Voltage rating: 600 V
• Poles: 3
• Series: QMB
• Manufacturer: Schneider Electric / Square D
• Part number: QMB3640
• Application: Non-fusible panelboard switch for lighting and distribution panelboards

Installation and usage notes

• The QMB3640 is designed to function in systems with appropriate upstream protection and fuse class. For optimal results, pair this switch with compatible upstream devices and follow standard electrical installation practices.
• It serves as a dependable, high-capacity switchboard unit within the QMB family, enabling straightforward integration into existing panelboards and new builds alike.

Who benefits most from this setup? Facilities engineers, electrical contractors, and building operators responsible for lighting and distribution across offices, manufacturing floors, and other large spaces where reliable three-phase switching and protection coordination are essential. By choosing the QMB3640, you gain a proven, career-tested solution from a trusted brand that prioritizes performance, compatibility, and long-term reliability. Available from AmpState, this panelboard switch helps you keep power distribution efficient and safe as demand grows.