Square D HJA36040 - 40 A, 600 V, 3-Pole Plug-In Circuit Breaker | AmpState

Discover dependable branch circuit protection with the Square D HJA36040 — a 40 A, 600 V, 3-pole plug-in molded case circuit breaker designed for fast, reliable protection in panelboards and load centers. Built for electricians who value speed, safety, and consistency, this breaker keeps your electrical systems guarded against overloads and short circuits without slowing you down on installation or maintenance.

Why this breaker stands out

• Fast plug-in connection for rapid installation and straightforward replacement, minimizing downtime during panel servicing or upgrades.
• Thermal-magnetic trip unit delivers stable, repeatable protection by combining thermal overload sensing with magnetic short-circuit triggering — reducing nuisance trips and ensuring prompt response when faults occur.
• OEM-compatible design engineered to work seamlessly with matching Square D OEM load centers and panelboards, helping maintain system integrity and simplifying stocking decisions.
• Versatile for multiple settings ideal for residential panels, commercial installations, and light industrial applications where reliable, code-compliant protection is essential.

Technical details

• Manufacturer: Square D
• Part Number: HJA36040
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 40 A
• Voltage Rating: 600 V
• Number of Poles: 3
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Ideal use cases

• Upgrading or repairing panelboards in residential or light commercial buildings where reliable 3-pole protection is required
• New installations in commercial spaces that demand fast, tool-free plug-in replacement during maintenance
• Systems requiring compatible protection with OEM load centers to ensure coordinated performance and safety compliance

Practical guidance for deployment

When selecting this breaker, ensure your panelboard is designed for plug-in, 3-pole devices of the HJA series and that the 40 A, 600 V rating aligns with the circuit requirements. For service life and safety, pair this unit with properly rated conductors and protective devices within the same electrical system to maintain coordinated protection across the panel.

Equip your electrical installation with a dependable, easy-to-service solution that keeps downtime to a minimum and protection to the maximum. The Square D HJA36040 is a precise, purpose-built choice for professionals who demand consistent performance from their circuit protection components.