Square D QOB2151021 - 15 A, 2-Pole Bolt-On Circuit Breaker | AmpState

Meet the Square D QOB2151021 — a dependable 15A, 2-pole bolt-on molded case circuit breaker designed to protect your electrical system with precision. Built for panelboards and load centers, this unit delivers reliable branch circuit overcurrent and short-circuit protection in a compact, rugged package.

• Secure bolt-on mounting provides a rigid, vibration-resistant bus connection. This means fewer micro-movements, less risk of arcing, and steadier performance in demanding environments where panels may experience vibration or movement.
• Thermal-magnetic trip unit combines a thermal element for steady overload protection with a magnetic element for rapid response to high-energy faults. The result is stable, repeatable protection that helps safeguard wiring, devices, and occupants.
• OEM-compatible design is engineered to fit matching Square D load centers and panelboards, ensuring proper fit, timing, and coordinated trip characteristics for seamless system protection.
• Versatile application ideal for residential, commercial, and light industrial circuits that require reliable, code-compliant branch circuit protection.

Technical specifications at a glance

• Manufacturer: Square D
• Part Number: QOB2151021
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 15 A
• Number of Poles: 2
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Why this breaker stands out

Unlike generic substitutes, the QOB2151021 is purpose-built for Square D panelboards, which means you’ll enjoy a precise trip curve, guaranteed fit, and dependable performance over the life of the installation. The combination of bolt-on mounting and a robust molded-case construction translates to a more durable connection in environments where equipment is subjected to vibration, temperature changes, or routine maintenance.

Use cases and ideal installations

• New installations in residential service panels where a compact, reliable 2-pole breaker is required for multiwire branch circuits or 120/240V services.
• Retrofitting or upgrading older panelboards in small commercial spaces, ensuring continued protection with OEM-compatible components.
• Light industrial setups where consistent protection for lighting circuits, receptacle banks, or dedicated equipment is essential, and panel durability matters.

Practical considerations and best practices

• Ensure compatibility by selecting a matching Square D OEM load center or panelboard to preserve coordinated protection and accurate trip settings.
• When installing, follow standard electrical practice for bolt-on breakers: disconnect power, secure the breaker firmly to the bus, and verify that the mounting hardware remains tightened to the manufacturer’s guidelines.
• Use this breaker for branch circuits requiring reliable protection against overloads and short circuits, especially in environments where panel vibration is a factor or periodic maintenance occurs.

In short, the Square D QOB2151021 delivers targeted, durable protection for a range of electrical installations. Its bolt-on design, thermal-magnetic protection, and OEM-fitment make it a practical choice for professionals seeking dependable performance without compromise. If you’re upgrading panelboard protection or replacing aging devices, this 2-pole, 15A breaker offers the right balance of reliability, compatibility, and ease of installation to keep your electrical system safe and compliant.