Square D QOB3301021 - 30A, 240VAC, 3-Pole, Circuit Breaker

Meet the Square D QOB3301021 — a purpose-built 30A, 240VAC, three-pole circuit breaker engineered for demanding electrical environments.

Designed for three-phase protection, it helps motor control centers, panelboards, and switchboards shut down faults quickly and safely—protecting wiring, motors, and control circuitry from overloads and short circuits.

Key specifications

• Current rating: 30A
• Voltage rating: 240VAC
• Poles: 3-Pole
• Configuration: Circuit Breaker (QOB family)

Ideal applications

Industrial, commercial, and OEM applications where three-phase protection is essential. Suitable for distribution panels, motor control centers, and equipment enclosures that require reliable, coordinated tripping across all phases.

What makes this model unique

• 3-Pole coordination ensures all phases trip together on fault, reducing equipment damage and downtime compared with single- or two-pole substitutes in three-phase circuits.
• Square D lineage offers proven reliability and compatibility with existing Square D protection systems, simplifying integration in legacy and new builds.
• Compact, versatile form fits standard enclosure footprints and supports a range of control-panel layouts without compromising protection.

Who benefits

Electrical engineers, panel builders, service technicians, and OEM designers selecting robust, standardized protection for 30A, 240V three-phase circuits in commercial, industrial, and manufacturing settings.

Best practices and tips

• Confirm panelboard and bus compatibility with QOB-series breakers to ensure seamless mounting and electrical contacts.
• In high-load motor circuits, schedule periodic inspections for signs of heating or nuisance trips, and ensure correct breaker sizing against motor starting currents.