Square D QOB320 - 20 A, 240 V, 3-Pole Bolt-On Circuit Breaker | AmpState

The Square D QOB320 delivers reliable, three-pole protection for 240V circuits in panelboards and load centers. Engineered as a bolt-on molded case circuit breaker, this 20A device provides robust overcurrent and short-circuit protection with a focus on secure, long-lasting performance in demanding electrical environments.

Why the QOB320 stands apart

• Secure bolt-on mounting – engineered for a rigid, vibration-resistant bus connection that stays locked in even in challenging installations.
• Thermal-magnetic trip unit – delivers stable, repeatable protection by sensing both overcurrent and abrupt short-circuit events, helping prevent nuisance trips while ensuring fast response when real faults occur.
• OEM-compatible design – engineered to pair with matching Square D OEM load centers and panelboards for straightforward upgrades, replacements, or retrofits.
• Versatile application – suitable for residential, commercial, and light industrial settings where dependable 3-pole protection at 240V is needed.

Ideal use cases

Use the QOB320 in panelboards and load centers that require solid 3-pole protection for 240V circuits. It’s well-suited for three-phase applications, equipment feeds, and branch circuits where reliability and consistent trip performance matter—whether you’re wiring a home electrical panel, a small business, or light industrial gear networks.

What you get and how it helps

• 20A capacity ensures appropriate protection for circuits that demand reliable, moderate current handling without frequent trips.
• 240V operation matches typical residential multi-wire and commercial 3-phase layouts, supporting a wide range of equipment and appliances.
• 3-pole configuration provides coordinated protection across all three conductors in suitable systems, helping to guard against multi-line faults.
• Bolt-on convenience simplifies installation into compatible panelboards, delivering a solid mechanical connection that supports ongoing reliability.

Technical snapshot

• Manufacturer: Square D
• Part Number: QOB320
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 20A
Voltage Rating: 240V
• Number of Poles: 3
• Mounting Style: Bolt-on
• Application: Branch circuit overcurrent and short-circuit protection

Upgrade or maintain panelboard protection with a device that emphasizes a sturdy mechanical connection, precise trip behavior, and compatibility with Square D load centers. The QOB320 is a focused solution for dependable 240V, 3-pole protection in a variety of settings—delivering clarity of protection and peace of mind for your electrical infrastructure.