Square D LX36400 - 400 A, 3-Pole Plug-In Circuit Breaker | AmpState

Introducing the Square D LX36400 - 400 A, 3-Pole Plug-In Molded Case Circuit Breaker from AmpState. Engineered for dependable branch circuit overcurrent and short-circuit protection, this unit is designed to live in panelboards and load centers where fast, secure protection matters most. Whether you’re upgrading an older panel or stocking for installations, the LX36400 delivers a reliable safeguard for demanding electrical systems.

Why the LX36400 stands out

• Fast plug-in connection for quick installation and effortless replacements, reducing downtime during servicing or panel upgrades.
• Thermal-magnetic trip unit provides stable, repeatable protection performance across a range of loads and ambient temperatures, minimizing nuisance trips while safeguarding circuitry.
• OEM-compatible design with matching Square D load centers and panelboards ensures a precise fit, proper electrical clearance, and reliable long-term operation.
• Versatile for multiple sectors suitable for residential, commercial, and light industrial applications, where robust 3-pole protection is essential for three-phase circuits.

Technical specifications at a glance

• Manufacturer: Square D
• Part Number: LX36400
• Type: Thermal-magnetic molded case circuit breaker
• Amperage Rating: 400 A
• Number of Poles: 3
• Mounting Style: Plug-in
• Application: Branch circuit overcurrent and short-circuit protection

Practical use cases and benefits

In residential settings, the LX36400 is ideal for protection in main distribution panels that feed high-draw loads such as HVAC equipment, electric water heaters, and large subpanels. For commercial spaces, it serves as a reliable safeguard for three-phase distribution in storefronts, offices, and service areas where consistent trip characteristics protect equipment and occupants alike. In light industrial environments, this breaker delivers dependable protection for motor circuits and heavy lighting loads, helping prevent costly downtime due to short circuits or overloads.

What makes it the right choice

Choosing a plug-in solution like the LX36400 reduces installation complexity and downtime. Its 3-pole design ensures simultaneous disconnection of all live conductors, enhancing safety and compliance in panelboard configurations. The thermal-magnetic trip mechanism provides a predictable response to overloads and short circuits, giving technicians and facility managers confidence in protection performance across a range of operating conditions. When you need a like-for-like, OEM-compatible replacement that maintains panel integrity and protection curves, this Square D breaker stands out.

Who should consider this breaker

• Electrical contractors performing panel upgrades or replacements in residential, commercial, or light industrial projects
• Facilities managers maintaining existing panelboards that require robust 400 A, 3-pole protection
• Systems integrators seeking reliable, OEM-aligned components for three-phase electrical distributions

Installation and compatibility notes

For best results, pair the LX36400 with compatible Square D load centers and panelboards. The plug-in design streamlines installation and service calls, enabling swift exchanges without altering wiring configurations. Always verify panel compatibility and follow standard electrical safety practices during installation or replacement.