Eaton / Westinghouse LB3150 Molded Case Circuit Breaker

This L-frame breaker is designed as a direct drop-in component for legacy Westinghouse panelboards, switchboards, and motor control centers.

Yes, the Eaton FD3150 can serve as a substitute. However, using the original LB3150 L-frame breaker avoids the need for retrofit adapter kits in older Westinghouse enclosures.

It features a thermal-magnetic trip unit with a fixed thermal element for long-time overload protection and an adjustable magnetic element for instantaneous short-circuit protection. This allows you to tune the short-circuit response to coordinate with downstream devices.

Yes. Eaton acquired the Westinghouse electrical distribution division, so breakers labeled under the Eaton, Cutler-Hammer, or Westinghouse brands with the LB3150 part number are the exact same L-frame component.

As a bolt-on breaker, it secures directly to the busbars in compatible Westinghouse enclosures. If you are replacing an existing LB3150, you can typically reuse the existing bus connections, but verify that the contact surfaces are clean and properly torqued.

The LB3150 L-frame breaker measures approximately 5.5 inches wide, 4.06 inches deep, and 10.125 inches high. Verify these dimensions against your available enclosure space before installation.

Always de-energize the panelboard or switchboard before installation. Verify that the available fault current at the line terminals does not exceed the interrupting capacity of the breaker for your specific system voltage, and ensure all bolted connections are properly torqued to prevent arcing.