Square D QO3401021 - 40 A, 240 V, 3-Pole Plug-In Circuit Breaker | AmpState

Meet the Square D QO3401021 — a 40A, 240V, 3-pole plug-in circuit breaker from the trusted Square D QO family. Engineered for dependable branch circuit protection in panelboards and load centers, this molded-case breaker delivers reliable overcurrent and short-circuit protection for demanding 240V circuits. Sold by AmpState, it’s a smart choice for professionals and serious DIYers alike.

Why this breaker stands out

• Fast plug-in connection for quick installation and effortless field replacement, minimizing downtime in service or upgrades.
• Thermal-magnetic trip unit delivers stable, repeatable protection across a range of operating conditions, reducing nuisance trips and ensuring consistent performance.
• OEM panel compatibility is designed to fit matching Square D load centers and panelboards, helping ensure proper fit, electrical integrity, and reliable operation.
• Versatile for multiple environments suitable for residential, commercial, and light industrial applications where robust 240V protection is required.

Ideal use scenarios

• New installations or panel upgrades in homes, offices, or small businesses that rely on three-pole protection for 240V circuits.
• Replacing aging or worn plug-in breakers within compatible Square D panels to restore dependable protection without rewiring.
• Motor loads, HVAC equipment, or other 240V appliances in light industrial settings that demand reliable, repeatable trip performance.

Technical specifications at a glance

• Manufacturer: Square D
• Part Number: QO3401021
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40 A
• Voltage Rating: 240 V
• Number of Poles: 3
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

With its plug-in design, reliable thermal-magnetic protection, and seamless compatibility with Square D panel centers, the QO3401021 is a practical, long-lasting solution for safeguarding critical circuits. Add it to your setup to ensure quick protection, easy maintenance, and dependable performance in both new and retrofit projects.