Square D LHL36400 - 400 A, 600 V, 3-Pole Circuit Breaker | AmpState

Meet the Square D LHL36400 — a rugged, three-pole molded case circuit breaker built to safeguard panelboards and load centers with dependable branch circuit overcurrent and short-circuit protection. Engineered for performance in demanding environments, this 400 A, 600 V breaker delivers precise protection where it matters most.

• Amperage rating: 400 A
• Voltage rating: 600 V
• Poles: 3
• Type: Thermal-magnetic molded case circuit breaker
• Part number: LHL36400
• Application: Branch circuit protection in panelboards and load centers

Why the Square D LHL36400 stands out

This breaker uses a thermal-magnetic trip unit that combines a stable thermal element with an instantaneous magnetic response. The result is repeatable protection that adapts to varying loads and ambient conditions, reducing nuisance trips while still delivering rapid disconnection during short-circuit events. The molded case design is compact, optimizing panel real estate and simplifying wiring layouts in both retrofit and new installations.

Key benefits in real-world use

• Space-efficient protection: Its compact form factor makes it easier to fit within crowded panelboards and load centers, helping you maximize usable panel capacity.
• Reliable, repeatable protection: Thermal-magnetic trip offers predictable response across a wide range of loads and temperatures, improving overall electrical safety for both residential and commercial applications.
• OEM-compatible performance: Designed to pair with matching Square D OEM load centers and panelboards, ensuring correct fit, coordination, and trip characteristics without additional adapters.
• Versatile application: Ideal for residential service panels, commercial distribution, and light industrial installations where robust branch-circuit protection is required.

Ideal use scenarios

Use the Square D LHL36400 when you need dependable protection for large branch circuits up to 400 A in panelboards and load centers. It’s well-suited for upgrading aging protection schemes, supporting new equipment zones, or consolidating circuits in spaces with limited panel room. Its 3-pole design is particularly relevant for three-phase distribution segments or multi-wire branch circuits that demand coordinated protection.

Installation and compatibility notes

Choose the LHL36400 when you require a direct, compatible match with Square D OEM panelboards and load centers. The 3-pole configuration and 400 A rating align with standard distribution practices, making retrofits straightforward. Always verify that the installed unit is the correct part number for your panel model to ensure seamless mechanical fit and electrical coordination.

What to expect in operation

In daily use, you’ll experience predictable trip behavior during overloads and fast interruption during short circuits, which helps protect conductors, devices, and overall electrical distribution. The breaker’s design supports long-term reliability with minimized maintenance when installed in appropriate environments and kept within its rated electrical and temperature specifications.

Upgrade your panel protection with the Square D LHL36400 to combine space-conscious design, reliable thermal-magnetic protection, and OEM-panel compatibility in a single, dependable package.