Square D QOB2125 - 125 A, 240 V, 2-Pole Bolt-On Circuit Breaker | AmpState

Square D QOB2125 is a 125A, 240V, 2-pole bolt-on molded case circuit breaker engineered for dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers.

Secure bolt-on mounting delivers a rigid, vibration-resistant bus connection, helping maintain consistent electrical performance even in installations with dynamic loads or in commercial environments.

Thermal-magnetic trip unit provides stable, repeatable protection across a range of operating conditions. The thermal element handles gradual overloads, while the magnetic element provides fast response to high-current faults, limiting damage and downtime.

OEM compatibility—designed to be used with matching Square D OEM load centers and panelboards, ensuring proper fit, trip characteristics, and coordinated protection within your distribution system.

Ideal for residential, commercial, and light industrial applications where reliable protection is essential.

Key specifications

• Manufacturer: Square D
• Part Number: QOB2125
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 125A
• Voltage Rating: 240V
• Number of Poles: 2
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Use cases and installation scenarios

The QOB2125 is well-suited for replacing or upgrading breakers in existing panelboards and load centers that require a reliable 125A, 240V, 2-pole solution. Use it in service panels, subpanels, or feeder configurations where a compact, bolt-on device reduces movement and improves safety in tight enclosures. Its precise thermal-magnetic trip response helps minimize nuisance trips while still delivering fast magnetic protection during high-current faults.

Practical considerations

• Compatibility: Ensure you’re pairing with the corresponding OEM load center or panelboard to maintain coordinated protection and fit.
• Reliability: The bolt-on design minimizes bus connection looseness due to vibration, supporting long-term performance in industrial and commercial settings.
• Replacement strategy: For upgrades or replacements, verify the panel’s bus configuration and available space for a 2-pole, bolt-on device.

Who benefits most

Electrical contractors, facility managers, and property owners who rely on stable electrical distribution with straightforward installation will appreciate the Square D QOB2125. It offers predictable protection, seamless integration with Square D panels, and a rugged form factor designed for busy environments.