Square D QOB3501021 - 50 A, 3-Pole Bolt-On Circuit Breaker | AmpState

The Square D QOB3501021 is a 50A, 3-pole bolt-on molded case circuit breaker designed to deliver reliable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Its secure bolt-on mounting creates a rigid, vibration-resistant bus connection, helping ensure consistent protection even in environments with equipment vibration.

Engineered for precise, dependable protection

• Thermal-magnetic trip unit provides coordinated thermal overload and magnetic short-circuit protection, delivering fast, repeatable trips and reducing nuisance interruptions.
• 3-pole configuration supports 3-phase circuits, making it suitable for motors and equipment common in commercial and light industrial applications.
• Bolt-on mounting establishes a solid, secure connection to the panel’s bus, enhancing reliability and ease of installation in compatible enclosures.
• OEM compatibility is designed to match Square D panelboards and load centers, ensuring proper fit, safe operation, and straightforward replacement in existing systems.

What problems it solves

This breaker protects critical electrical infrastructure by preventing damage from overcurrent and short circuits. The combination of a robust bolt-on mount and a thermal-magnetic trip unit reduces the risk of intermittent trips due to vibration or inconsistent connections, helping to minimize downtime in residential, commercial, and light industrial settings.

Key specifications

• Manufacturer: Square D
• Part Number: QOB3501021
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 50 A
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Ideal for who and where

Perfect for electrical professionals and facilities managers overseeing panelboards and load centers in residential, commercial, and light industrial environments. If you’re upgrading or replacing a 50A, 3-pole bolt-on breaker in Square D or compatible OEM panels, the QOB3501021 offers a reliable, code-compliant solution with long-term performance.

Available through AmpState, the Square D QOB3501021 50A 3-pole bolt-on breaker is ready to install in compatible panelboards and load centers, delivering the protection your circuits demand.