Square D QO340GFI - 40 A, 240 V, 3-Pole Plug-In Circuit Breaker | AmpState

Introducing the Square D QO340GFI — a 40A, 240V, 3-pole plug-in molded case circuit breaker designed to deliver dependable branch circuit protection for panelboards and load centers. This unit is built to handle everyday demand in residential, commercial, and light industrial environments, combining quick installation with reliable performance.

Why this model stands out

• Fast plug-in connection: Snap-in installation reduces downtime during replacement or upgrades, so you stay up and running with minimal interruption.
• Thermal-magnetic trip unit: Delivers stable, repeatable protection across a range of loads and conditions, helping prevent nuisance trips and protecting connected equipment.
• 3-pole at 240V: Ideal for 3-phase systems and multi-wire branch circuits in compatible panelboards, consolidating protection in a single, compact device.
• Molded-case durability: Robust construction designed to withstand the rigors of commercial and light industrial use while preserving long service life.
• OEM panel compatibility: Engineered to fit and coordinate with matching Square D load centers and panelboards for dependable electrical alignment.

Practical use cases

• Replacing a failed breaker in existing Square D panelboards to restore circuit protection quickly.
• Protecting critical 3-pole 240V circuits in small commercial spaces or light industrial setups where reliable protection is essential.
• Retrofit or new installations where a plug-in solution minimizes panel downtime and simplifies future maintenance.
• Steady protection for branch circuits serving motors, HVAC equipment, or other 240V loads requiring robust, predictable trip behavior.

Technical specifications

• Manufacturer: Square D
• Part number: QO340GFI
• 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

Who is it for and what problems does it solve?

Designed for electricians, facilities managers, and property owners who need fast, reliable protection for 3-pole 240V circuits, the QO340GFI keeps critical systems safeguarded with minimal installation downtime. Its plug-in design and OEM compatibility reduce commissioning effort and ensure consistent protection across Square D panel ecosystems. If you’re upgrading a panel or replacing a failing breaker, this unit provides a precise fit, predictable trip behavior, and long-term reliability you can trust.

Note: Always ensure compatibility with your specific panelboard model and follow local electrical codes. Installation should be performed by a licensed electrician.