Square D | ME36400LSG | Circuit Breaker | 400A | 3-Pole | 600V

Square D ME36400LSG circuit breaker delivers robust protection for 600-volt, three-phase power systems. With a 400-amp rating and a 3-pole design, this unit is built for maintenance, retrofit, and replacement projects where exact compatibility matters, helping you keep critical equipment running smoothly.

• Amperage: 400 A
• Poles: 3-Pole
• Voltage rating: 600 V
• Part number: ME36400LSG
• Manufacturer: Square D

Who it's for

Ideal for facilities managing industrial-grade, 600V three-phase distributions—manufacturing floors, data centers, and commercial/industrial panels. Whether you're upgrading an aging main disconnect, performing a retrofit to accommodate higher load demands, or replacing a failed unit, this breaker provides reliable, drop-in compatibility within the Square D ecosystem.

What makes this model unique

• Exact compatibility with Square D panels and bus layouts thanks to its clearly defined part number reference, reducing guesswork during retrofits and replacements.
• Three-pole protection ensures synchronized shutdown across all phases, supporting balanced protection in demanding 600V environments.
• Designed to meet the practical needs of industrial maintenance by pairing a straightforward 400A main-disconnect solution with the familiar Square D operating characteristics you rely on.

Practical use cases

• Replacement in an existing 600V, 3-phase distribution panel where ME36400LSG is specified as the required part.
• Retrofit of legacy systems to restore reliable protection and streamline future maintenance cycles.
• New installations in setups requiring a 400A, 3-pole main breaker within a 600V service perimeter.

Important notes for ordering and installation

Before purchasing, confirm fit and ratings using the ME36400LSG part number as the best reference for compatibility. Verify amperage, voltage, and pole configuration against your panel’s labeling and system requirements. Follow all local electrical codes and the panel manufacturer’s installation guidelines for mounting, wiring practices, and safety.

Choose this Square D model when you need a dependable, properly referenced 400A main breaker that aligns with your 600V, three-phase electrical infrastructure, delivering predictable protection and streamlined maintenance for years to come.