Square D QO345 - 45 A, 240 V, 3-Pole Plug-In Circuit Breaker | AmpState

Meet the Square D QO345 — a 45A, 240V, 3-pole plug-in molded case circuit breaker designed to guard your electrical system with fast, reliable protection. Built for dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers, this breaker is ready to drop into compatible OEM panels for immediate protection.

• Fast plug-in connection for quick installation and effortless replacements, minimizing downtime during upgrades or service calls.
• Thermal-magnetic trip unit delivers stable, repeatable protection by sensing both overload and short-circuit conditions, reducing nuisance trips and ensuring consistent performance.
• OEM compatibility designed to work with matching Square D OEM load centers and panelboards, ensuring proper fit, trip curves, and labeling.
• Versatile applications suitable for residential, commercial, and light industrial environments where reliable 3-pole 240V protection is required.

Key specifications

• Manufacturer: Square D
• Part Number: QO345
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 45A
• Voltage Rating: 240V
• Number of Poles: 3
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Why this matters: In panelboard and load center setups, reliable overcurrent protection is essential to prevent wiring damage, nuisance trips, and potential fires. The QO345 combines a robust molded case with a precise thermal-magnetic trip to deliver dependable protection when you need it most, without complicating future panel upgrades or replacements.

Use scenarios include upgrading residential panels to support additional circuits, outfitting commercial distribution boards with a scalable 3-pole 240V solution, or replacing aging breakers in light industrial installations. Its plug-in design makes swapping out old breakers straightforward, reducing downtime and enabling quick maintenance windows.

If you’re aligning with Square D’s QO series, the QO345 offers a confident, spec-matched choice that pairs with compatible OEM panels to maintain the integrity of your protection scheme. Choose this 3-pole 45A 240V plug-in breaker when you need solid, dependable protection that’s easy to install and backed by a trusted brand.