Square D | LRA36400U33X | Circuit Breaker | 400A | 3-Pole | 600V

Square D's LRA36400U33X is a rugged 400A, 3-pole circuit breaker engineered for reliable protection of 600V three-phase electrical systems. Designed for maintenance, retrofit, and replacement projects, this unit delivers dependable performance where exact specifications matter most, helping you keep critical equipment running safely and efficiently.

Key specifications at a glance

• Amperage: 400A
• Poles: 3-Pole
• Voltage rating: 600V
• Reference / part number: LRA36400U33X
• Compatibility note: Confirm fit and ratings before ordering — the part number is the best reference for compatibility.

Why this unit stands out

Unlike generic breakers, the LRA36400U33X is purpose-built for Square D installations, offering precise form, fit, and function for three-phase 600V distributions. It supports steady protection in demanding environments and integrates smoothly with existing Square D panels and bus configurations, reducing misfit risk during retrofits and replacements. This is a practical choice when you need a trusted, official reference that aligns with your current electrical infrastructure.

Ideal use cases

• Retrofit projects where existing panels require a 400A, 3-pole, 600V protection device with a proven compatibility track record.
• Maintenance replacements to restore original protection characteristics without panel modifications.
• New installations in commercial or industrial settings that operate high-current, three-phase 600V circuits.

Installation & compatibility tips

To ensure reliable performance, verify that the panel’s catalog and bus arrangement match the LRA36400U33X specifications. Since the part number is the best reference for compatibility, cross-check it against your panel's documentation before procurement. If you're upgrading from an older unit, plan for a straightforward swap by aligning mounting, wiring terminals, and trip characteristics with your existing setup.

Care and handling

Handle with clean, dry hands and store in a dry area prior to installation. De-energize the circuit and follow standard electrical safety practices during replacement or retrofit work. After installation, perform a controlled test to confirm proper operation within your system’s protection scheme.