Square D LX36400G Molded Case Circuit Breaker

The LX36400G is designed exclusively for use in Square D I-Line panelboards and switchboards. It features a specialized plug-on jaw connection for the line side and requires dedicated legacy L-frame mounting space on the bus stack.

The "G" indicates the inclusion of Ground-Fault protection. The electronic Micrologic trip unit on this model provides complete LSIG functions, which stand for Long-Time, Short-Time, Instantaneous, and Ground-Fault protection.

It utilizes Square D's I-Line plug-on design. The breaker features blow-on jaw connectors that ratchet firmly onto the panelboard bus stack. It is then secured in place with a retaining screw, meaning no separate bus connectors or cables are required for the line side.

The legacy LX series has been superseded by the Square D PowerPacT L-Frame series. When replacing an LX36400G with a modern equivalent like the LJA36400U44X or LJA36400U43X, an HNM1BL filler plate must be installed to compensate for the smaller physical footprint of the newer breaker in the existing I-Line enclosure.

Yes. Because it utilizes a solid state electronic trip unit rather than fixed thermal-magnetic elements, the user can adjust the pickup and delay settings across the long-time, short-time, instantaneous, and ground-fault parameters to achieve exact selective coordination within the power system.

The standard load side lugs accept either one conductor from 1 AWG to 600 kcmil, or two conductors from 1 AWG to 250 kcmil per phase. The terminals are rated for terminating both copper and aluminum wire.