Square D LX36125 Circuit Breaker

This breaker is engineered specifically for Square D I-Line panelboards and switchboards. It utilizes a plug-in connection that mounts directly to the I-Line busbar, making it incompatible with standard unit-mount or load center applications.

The LSI designation means the breaker features adjustable Long-Time, Short-Time, and Instantaneous trip settings. This solid state technology allows panel builders to fine-tune the trip curve for precise selective coordination with downstream devices.

The factory lugs accommodate either a single conductor from 1 AWG up to 600 kcmil, or dual conductors ranging from 1 AWG to 250 kcmil. The terminals are rated for both copper and aluminum wiring.

The LX series is a legacy L-Frame breaker. For modern upgrades, Schneider Electric typically transitions users to the PowerPact L-Frame series. However, sourcing an exact LX36125 replacement avoids the need for bus modifications in older I-Line gear.

While its primary rating is 65kAIC at 480V, the LX36125 is fully rated to interrupt up to 100kAIC when installed on a 240V AC system.

No. The I-Line plug-in design features integrated jaws that clamp directly onto the panelboard bus assembly, requiring no external mounting brackets for the electrical connection.

Unlike standard thermal-magnetic breakers, the solid state electronic trip unit provides highly accurate and repeatable trip curves. It is less susceptible to ambient temperature fluctuations, ensuring reliable overcurrent protection in demanding environments.