Square D LXI36400G Circuit Breaker

This breaker features an I-Line style plug-in connection and is exclusively designed for use in Square D I-Line panelboards and switchboards. It will not fit in NQ, NF, or QO series panels.

The standard load-side lugs on the LXI36400G accept either one 500 to 750 kcmil wire or two 3/0 AWG to 250 kcmil wires per phase. These lugs are rated for both aluminum and copper conductors.

The "G" indicates that the breaker includes integral ground fault protection. This is the "G" in the LSIG designation of its solid-state Micrologic trip unit, which also provides Long-Time, Short-Time, and Instantaneous protection.

The LXI series is a legacy molded case circuit breaker frame. While exact replacements like the LXI36400G are sourced for existing I-Line panels, Square D has transitioned to the PowerPact L-frame series for modern installations.

The I-Line plug-in design allows the line side of the breaker to mount directly onto the panelboard bus stack, eliminating the need for line-side cabling. The connection utilizes a blow-on jaw design that magnetically grips the bus tighter during high-fault conditions.

This breaker is equipped with a solid-state Micrologic electronic trip unit. Unlike standard thermal-magnetic breakers, the electronic trip unit allows for precise adjustability of the trip curve parameters to coordinate with other devices in the electrical system.

Yes, the LXI frame is a current-limiting molded case circuit breaker. It is engineered to clear faults extremely fast, reducing the peak let-through current and energy to protect downstream equipment in high-fault environments.