Westinghouse Circuit Breaker Cross-Reference

Westinghouse's molded-case breaker line became Cutler-Hammer and then Eaton, so the modern path for a Westinghouse FB, KB, LB, Tri-Pac, or Series C breaker is the equivalent current Eaton frame, selected by amp and interrupting rating. The originals are long discontinued; Edmundson Industrial sources new-surplus, used-tested, and reconditioned Westinghouse breakers and cross-references them to the Eaton successors.

Legacy frame → modern replacement

Legacy frame	Amp range	Current path	Example catalog
FB (F-frame)	to 100 A	Eaton F-frame successor	FB-series (confirm on nameplate)
KB (K-frame)	to 225 A	Eaton K-frame successor	KB-series (confirm on nameplate)
LB (L-frame)	to 600 A	Eaton L-frame successor	LB-series (confirm on nameplate)
Tri-Pac / Series C	varies by frame	Current Eaton	by catalog

Amp ranges are nominal: the catalog number encodes poles, voltage, amp rating, and interrupting class. Confirm against the nameplate before substituting.

How do you read a Westinghouse catalog number?

Westinghouse molded-case numbers carry a frame code (FB, KB, LB…) plus digits for poles and amp rating. Because the line passed to Cutler-Hammer and Eaton, many Westinghouse frames have a direct Eaton successor, but confirm the interrupting rating and mounting against the nameplate, since these are not always identical.

Catalog	Frame / type	Notes
FB-series	F-frame	to 100 A; maps to Eaton F-frame
KB-series	K-frame	to 225 A; maps to Eaton K-frame
LB-series	L-frame	to 600 A; maps to Eaton L-frame

Demand lives on the surplus market

Westinghouse breakers trade almost entirely on the surplus and reconditioned market now: Google volume is small, but the installed base in older switchgear is large. Availability and an honest condition call, not search traffic, are what get these jobs done.

Drop-in original or retrofit?

Because Westinghouse gear is old, a surplus original or its direct Eaton successor can avoid reworking the panel. When the Eaton successor's footprint differs, our fabrication side builds adapter and filler hardware so it lands in the Westinghouse opening: part and panel on one PO.

FAQ

Are Westinghouse breakers obsolete?

Yes: Westinghouse's molded-case line became Cutler-Hammer and then Eaton. Original frames (FB, KB, LB, Tri-Pac, Series C) are legacy; we source new-surplus, used-tested, and reconditioned units and cross-reference to the current Eaton successors.

What replaces a Westinghouse FB or KB breaker?

The equivalent current Eaton frame by amp and interrupting rating (Westinghouse F / K / L map to the Eaton F / K / L-class). We also source the original Westinghouse surplus.

Can you still get Westinghouse breakers?

Yes: through the surplus and reconditioned market. Send the catalog number and we'll quote condition and lead time.

Is Westinghouse the same as Cutler-Hammer and Eaton?

The molded-case lineage runs Westinghouse to Cutler-Hammer to Eaton. Parts and cross-references follow that path.

Will an Eaton breaker fit my Westinghouse panel?

Often, but footprints changed. Our fabrication side makes adapter and filler hardware so a current breaker fits the legacy opening.

Request a Quote

or send the catalog number off the breaker to sales@edmundsonindustrial.com · (832) 975-8827 · Houston, TX. Response timing is confirmed with the request.

Related cross-reference pages

Send the catalog number off the breaker.

Condition disclosed before sale. Response timing is confirmed with the request.

Request a Quote