Square D QOB340EPD - 40 A, 240 V, 3-Pole Bolt-On Circuit Breaker | AmpState

Meet the Square D QOB340EPD 40A, 240V, 3-pole bolt-on molded case circuit breaker — a purpose-built solution for dependable branch circuit protection in panelboards and load centers. Designed for rugged reliability in residential, commercial, and light industrial settings, this unit delivers precise protection where it matters most.

Key Features

• Secure bolt-on mounting provides a rigid, vibration-resistant bus connection, so your electrical system stays protected even in environments with movement or vibration.
• Thermal-magnetic trip unit delivers stable, repeatable protection by reacting to both overcurrent and short-circuit conditions, reducing nuisance trips and safeguarding sensitive equipment.
• OEM-compatible compatibility is designed to work with matching Square D load centers and panelboards, ensuring seamless integration and reliable performance.
• 3-pole design supports three-phase systems, making it suitable for a range of commercial and light industrial applications where balanced protection is critical.

What It Protects and Where It Fits

The QOB340EPD is a molded case circuit breaker intended for branch circuit overcurrent and short-circuit protection. Its bolt-on style makes it a robust choice for panelboards and load centers where space is at a premium and reliability cannot be compromised. Ideal for distributing power to lights, outlets, small motors, HVAC equipment, and other essential loads across residential and commercial environments.

Technical Snapshot

• Manufacturer: Square D
• Part Number: QOB340EPD
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40A
• Voltage Rating: 240V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Ideal Use Scenarios

• New panelboard installations or replacements in light commercial spaces requiring reliable 3-phase protection.
• Upgrading electrical distribution in small industrial setups where vibration resistance and durable mounting are essential.
• Residential-commercial hybrids with three-phase equipment or machinery connections that demand solid protection.
• Retrofits in OEM-compatible load centers where maintaining system performance without compatibility issues matters.

Why This Breaker Stands Out

Unlike generic solutions, the QOB340EPD combines a purpose-built bolt-on design with a thermal-magnetic trip system that remains predictable across long service lives. Its compatibility with matching OEM panels means fewer troubleshooting steps and faster commissioning. For facilities where downtime is costly, this breaker’s robust construction and precise trip characteristics help you maintain electrical safety and continuity.

Practical Tips for Getting the Most Out of Your Breaker

• Ensure your panelboard is designed to accept bolt-on breakers from the Square D QOB family to guarantee fit and performance.
• Use this 40A, 240V, 3-pole unit to protect three-phase circuits feeding motors, pumps, or HVAC components, balancing protection across all legs.
• Plan for easy future maintenance by pairing with compatible OEM load centers, reducing the risk of mismatched components during service calls.