Square D QMB363T - 100A, 600V, 3-Pole Panelboard Switch / Switchboard Unit | AmpState

The Square D QMB363T is a purpose-built fusible panelboard switch engineered to bring dependable, controlled power switching to lighting and distribution panelboards in commercial and light industrial environments. With a 100 A rating and a 600 V maximum, this three-pole unit from the QMB series delivers precise isolation and targeted overcurrent protection when paired with the appropriate upstream protection and fuse class. What sets the QMB363T apart

• Three-pole configuration for balanced 3-phase control—Designed to seamlessly manage three phases, simplifying wiring and ensuring uniform switching across all legs in 3-phase systems.
• Integrated fusible switching for targeted protection—Acts as a dedicated disconnect with built-in fusing when used with compatible fuse classes, enhancing fault isolation and downstream protection.
• Compact, panelboard-ready design—Engineered to fit within standard lighting and distribution panelboards, delivering reliable performance without expanding the footprint.
• Part of the established QMB/Square D ecosystem—Part Number QMB363T in the dependable QMB series, ensuring compatibility with existing panelboard configurations and maintenance practices.
• Upstream protection coordination—Built to work in concert with upstream protective devices to achieve selective tripping and coordinated protection across the electrical system.

Ideal uses and scenarios

• New installations in commercial buildings where a robust 3-phase disconnect with fusible protection is required for safety and reliable service isolation.
• Retrofits in lighting and distribution panelboards where clear isolation during maintenance is essential and downstream equipment benefits from targeted protection.
• Systems that demand predictable protection coordination through suitable fuse classes and upstream devices to ensure safe fault isolation and easier servicing.

How it fits into your electrical system The QMB363T is not a standalone breaker. It is a fusible panelboard switch designed for use with the correct upstream protection and fuse class. When integrated properly, it provides dependable load interruption, enhances fault isolation, and supports safer, more maintainable panelboard configurations. Always follow local electrical codes and manufacturer guidelines for mounting, wiring, and fuse compatibility to ensure optimal performance. Why choose this for your panelboard - Clean isolation for maintenance: The integrated fusible switch configuration offers straightforward disconnection of the load, making service work safer and faster. - Reliable 3-phase protection: With a 3-pole design, you gain balanced control across all phases, reducing the risk of unequal phase loading and improving system stability. - Flexible compatibility: As part of the Square D QMB family, you benefit from a familiar installation footprint and compatibility with existing panelboard ecosystems and upstream protection strategies. Specifications at a glance

• Amperage: 100 A
• Voltage: 600 V
• Poles: 3
• Series: QMB
• Manufacturer: Schneider Electric / Square D
• Part Number: QMB363T

Practical tips for installers and maintainers - Verify upstream fuse class compatibility before deployment to ensure correct coordinated protection and selective tripping behavior. - Confirm the panelboard enclosure dimensions and mounting provisions to guarantee a snug, code-compliant installation without overcrowding adjacent components. - Document the protection strategy used with this device to aid future maintenance and fault analysis, including fuse class, upstream devices, and the intended discharge path for faults. The QMB363T delivers a deliberate blend of robust 3-phase control, targeted fusible protection, and panelboard-ready practicality. It’s the practical choice for commercial lighting and distribution panelboards where reliable isolation, coordinated protection, and streamlined installation matter most.