Square D | LLL36400CU33X | Circuit Breaker | 400A | 3-Pole | 600V

Square D LLL36400CU33X is a rugged, high-current circuit breaker engineered for demanding 3-phase systems. With a 400A rating and a 3-pole configuration, this unit delivers reliable overcurrent protection for 600V electrical environments. Designed for maintenance, retrofit, and replacement projects where exact specifications matter, it helps you preserve system safety and continuity without guessing about compatibility.

• Amperage: 400A
• Poles: 3-Pole
• Voltage: 600V
• Part number: LLL36400CU33X
• Brand: Square D

Important fit notes: Confirm fit and ratings before ordering. The part number is the best reference for compatibility, ensuring you get a plug-in replacement that matches your panel’s protection profile.

Who is this ideal for? facilities and technicians managing industrial electrical systems that rely on robust 3-phase protection, such as manufacturing lines, large motors, processing equipment, and power distribution panels that operate at up to 600V. If your maintenance or retrofit project requires a precise 400A, 3-pole device within the Square D family, this breaker is designed to slot into compatible Square D panels without altering other protective components.

Why choose the LLL36400CU33X over generic replacements? its exact specifications align with existing 3-pole, 600V architectures, reducing the risk of mismatched trip characteristics or mounting incompatibilities. Using the correct part number helps maintain consistent protection coordination and minimizes downtime during replacements or upgrades.

Practical tips for installation and use:

• Verify that your panel label lists compatible Square D breakers for 3-pole, 400A, 600V service and that the LLL36400CU33X matches the referenced part number.
• Before installation, ensure the power is fully isolated and the area is prepared for safe handling of high-current devices.
• Keep a spare LLL36400CU33X on hand for planned maintenance to minimize panel downtime.
• Document the replacement in your panel maintenance log, noting the part number, voltage rating, and date of service to support future servicing.

In short, the Square D LLL36400CU33X delivers dependable, industrial-grade protection for 600V, 3-phase systems where exact specifications and reliable compatibility are non-negotiable. Use it for maintenance, targeted retrofits, or replacement in panels designed for Square D protection, and rest easier knowing your high-current circuit is covered by a proven, OEM-matched solution.