Square D QOU140 - 40 A, 120 V, 1-Pole Bolt-On Circuit Breaker | AmpState

Meet the Square D QOU140 — a 40A, 120V, 1-pole bolt-on molded case circuit breaker designed for dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Built to endure in dense electrical environments, it pairs precise protection with a robust mounting approach.

Why this matters in real-world panels: the bolt-on mounting delivers a rigid, vibration-resistant bus connection that stays tight through temperature swings and panel activity. The thermal-magnetic trip unit provides stable, repeatable protection—thermal protection for overloads and magnetic response for short circuits—reducing nuisance trips and safeguarding wiring and devices.

Compatibility isn’t an afterthought: this breaker is engineered to work with matching OEM Square D load centers and panelboards, ensuring a clean fit, accurate trip characteristics, and straightforward maintenance or expansion without compatibility surprises.

Key features and benefits

• Bolt-on mounting for secure, vibration-resistant connections that stay tight over time
• Thermal-magnetic trip unit for reliable overload and short-circuit protection
• 1-pole design with a 40A rating at 120V, ideal for standard branch circuits
• Molded case construction from a trusted Square D lineage for long-term reliability
• Designed for seamless compatibility with OEM load centers and panelboards

Ideal applications

• Residential panelboards: protect lighting, receptacle, and small appliance circuits with confidence
• Commercial settings: manage branch circuits for lighting and standard 120V equipment
• Light industrial environments: reliable protection for 120V-powered machinery and outlets

Technical specifications

• Manufacturer: Square D
• Part Number: QOU140
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40 A
• Voltage Rating: 120 V
• Number of Poles: 1
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Choose the Square D QOU140 when you need a dependable, easy-to-install solution that delivers precise protection in residential, commercial, or light industrial panels. It’s built to withstand the realities of real-world electrical systems, offering predictable performance when it matters most.