Square D FI36040 - 40 A, 600 V, 3-Pole Plug-In Circuit Breaker | AmpState

Meet the Square D FI36040 40 A, 600 V, 3-Pole Plug-In Circuit Breaker—designed to protect every branch circuit in panelboards and load centers with precision and ease. Available from AmpState, this breaker delivers quick service and reliable protection for residential, commercial, and light-industrial applications.

• Fast plug-in connection: snaps into compatible Square D load centers for rapid installation and straightforward replacement when service is required.
• Thermal-magnetic trip unit: provides stable, repeatable protection by responding to both overload and short-circuit conditions.
• 3-pole design for 3-phase systems: ideal for distributed power in commercial or light-industrial environments.
• OEM-compatible: engineered to fit matching Square D panelboards and load centers for seamless integration.
• Versatile across settings: suitable for residential, commercial, and light-industrial electrical protection needs.

Technical specifications

• Manufacturer: Square D
• Part number: FI36040
• 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

Use cases and scenarios

The FI36040 is designed to protect branch circuits across a range of environments:

• Residential panels where 3-phase distribution is present or for future upgrades with 3-pole protection.
• Commercial service equipment and distribution boards that require dependable 40 A protection at up to 600 V.
• Light-industrial machinery feeds where quick plug-and-play replacement reduces downtime during maintenance.

Installation, compatibility, and safety tips

Plug-in compatibility with Square D OEM load centers and panelboards means you can swap in a like-for-like breaker during upgrades or service calls without rewiring the enclosure. For best results:

• Turn off main power and verify the panel rating before installation.
• Use the correct 3-pole, 40 A configuration to support your three-phase circuits up to 600 V.
• Ensure the panelboard is listed for molded-case breakers of this type and that the bus connectors align for a secure, audible snap.

Why choose this Square D FI36040 at AmpState?

With a proven track record of reliable performance, Square D molded case breakers deliver consistent trip characteristics and durable construction. The FI36040’s fast plug-in design minimizes downtime during replacements, while the thermal-magnetic trip delivers predictable behavior across temperature and load conditions. When you need 3-pole protection that fits neatly into compatible panelboards and load centers, this 40 A, 600 V unit is a compelling choice for installers and facility managers who value speed, reliability, and ease of maintenance.