Square D LGA36400U31X 400A 3P 600V Circuit Breaker | AmpState

The Square D LGA36400U31X is a rugged, three-pole 400 A circuit breaker designed for panelboards, load centers, and broader electrical distribution systems. Built to support retrofit work and long-term maintenance planning, this unit keeps your projects streamlined by preserving the exact part number across replacements and service updates.

Key specifications

• Amperage: 400 A
• Poles: 3
• Voltage: 600 V
• Manufacturer: Square D
• Part Number: LGA36400U31X
• Applications: Circuit protection in panelboards, load centers, and electrical distribution systems

What makes this model stand out

Unlike generic replacements, the LGA36400U31X is purpose-built to integrate seamlessly with Square D panels and compatible accessories. Its 3-pole design supports three-phase electrical distributions, delivering dependable overcurrent protection for demanding industrial or commercial environments. The 600 V rating accommodates a wide range of distribution setups, enabling you to standardize protection across multiple panels without reinventing wiring configurations or trip characteristics.

Ideal use cases

• Retrofit projects where maintaining the exact part number simplifies ordering, documentation, and panel compatibility
• Spare stock for service fleets to reduce downtime during maintenance outages
• Repairs or upgrades in facilities that rely on Square D protection schemes and need consistent, predictable performance
• Panelboard and load center modernization without re-engineering electrical distribution layouts

Why choose AmpState

AmpState offers availability for the LGA36400U31X, helping you secure a precise match for your existing installations. If you’re unsure about compatibility with a particular panel, AmpState’s guidance is available to confirm fit based on the part number and system requirements, ensuring you don’t encounter unexpected rework.

In short, the Square D LGA36400U31X is a purpose-built, retrofit-friendly choice for 400 A, 3-pole, 600 V circuit protection. It delivers reliable performance within established Square D protection ecosystems, making maintenance and upgrades faster, simpler, and more predictable.