General Electric | MB133 | Circuit Breaker | 150A | 3-Pole | 277V

Meet the General Electric MB133 circuit breaker — a purpose-built solution for reliable overcurrent protection in commercial and industrial electrical systems. Designed for 150A, 3-pole operation at 277V, this unit is tailored for three-phase circuits, making it a precise fit for maintenance, retrofit, and replacement projects where exact specifications matter.

Why choose the GE MB133

• Precise compatibility: The MB133 part number is the best reference for ensuring your replacement matches your GE panels and system requirements.
• Three-phase protection: 3-pole design delivers balanced protection across all phases in 277V environments, helping safeguard motors, lighting, and other 277V equipment.
• Clear electrical rating: 150A uninterrupted operating capacity provides dependable protection for circuits with higher current demands.
• Designed for retrofit and maintenance: A straightforward replacement option when servicing legacy GE setups or upgrading existing infrastructure.

Key specifications at a glance

• Amperage: 150A
• Poles: 3-Pole
• Voltage: 277V
• Part number / model: MB133
• Manufacturer: General Electric (GE)

Use cases and ideal applications

Best suited for commercial and industrial panels that require consistent three-phase protection at 277V. It’s an excellent choice for retrofit projects where older GE equipment needs a like-for-like replacement, or for maintenance stock to minimize downtime during service events. Whether powering motor drives, HVAC equipment, or lighting circuits in a three-phase distribution setup, the MB133 provides reliable, spec-aligned performance.

How this part fits into your workflow

• Before you order: Confirm fit and ratings against your panel labeling and service blueprints. The MB133 is purpose-built; matching this exact reference helps ensure safe, compliant operation.
• During installation: Follow standard electrical safety practices and ensure the circuit is de-energized. Verify that the panel’s bus configuration and wiring match the 3-pole, 277V specification.
• Post-install tips: After replacement, perform a functional test to confirm proper tripping behavior and verify that downstream equipment operates as intended without nuisance trips.

Choose the GE MB133 for a dependable, spec-accurate replacement that aligns with GE systems and three-phase 277V applications. It’s a focused, practical part designed to keep critical electrical infrastructure running smoothly and safely.