Square D LGA36400U44X - 400 A, 3-Pole Plug-In Circuit Breaker | AmpState

Power your electrical panel with precision and speed using the Square D LGA36400U44X — a 400 A, 3-pole plug-in molded case circuit breaker engineered for reliable branch-circuit protection in panelboards and load centers. This unit delivers fast plug-in connection, making installation and replacements quicker and cleaner, especially during retrofit projects or panel upgrades.

Why this breaker stands out

• Fast plug-in connection — streamline installation and reduce labor time with a secure, tool-free plug-in fit that aligns perfectly with compatible panelboards and load centers.
• Thermal-magnetic trip unit — combines thermal overload protection with magnetic short-circuit protection, delivering stable, repeatable performance across varying loads and ambient conditions.
• 3-pole, 400 A design — ideal for large feeder circuits and commercial/industrial environments where robust protection is essential without sacrificing space in the panel.
• OEM-aligned compatibility — designed to work with matching Square D OEM load centers and panelboards, ensuring coordinated protection and easy replacement.

Technical snapshot

• Manufacturer: Square D
• Part Number: LGA36400U44X
• 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

Ideal applications and use cases

This plug-in breaker is purpose-built for residential, commercial, and light-industrial settings where large-diameter feeders require dependable protection. Use scenarios include:

• Upgrading panelboards to accommodate higher-capacity feeders without changing internal buswork
• Retrofitting aging electrical systems in commercial buildings to improve protection against faults and short circuits
• Serving as a reliable main/ feeder breaker in installations that demand quick swap-outs and minimal downtime
• Protecting critical equipment in mechanical rooms, data centers, and wellness facilities where stability matters

What makes it practical

Choosing the LGA36400U44X means selecting a solution that balances high-capacity protection with installation efficiency. The plug-in design minimizes field wiring complexity, reducing installation time and potential contact issues. The thermal-magnetic trip delivers consistent performance across diverse loads, so you can rely on predictable protection during peak demand or fault events. And because it’s designed to pair with matching OEM panels, you gain confidence in coordinated protection and easier future maintenance.

Whether you’re replacing an aging breaker, expanding a panel, or outfitting a new installation, this 400 A, 3-pole plug-in breaker from Square D offers the strength and reliability required for demanding electrical systems. AmpState brings you trusted protection that keeps facilities running smoothly.