Engineered for industrial applications, the Eaton FB4050L is a 4-pole, 50A molded case circuit breaker from the legacy F-Frame family. It provides dependable thermal-magnetic trip functions for robust system defense. This unit mount breaker integrates into Westinghouse and Cutler-Hammer Pow-R-Line C panelboards and motor control centers. It serves as a reliable replacement component, superseded by the FD4050. Rated 14kAIC at 480VAC, it features a non-interchangeable trip and reverse feed.
Which panelboards are compatible with the FB4050L circuit breaker?
This four-pole breaker is designed for use in Westinghouse and Cutler-Hammer Pow-R-Line C panelboards, FDP panelboards, switchboards, and motor control centers.
What wire sizes are accepted by the standard lugs on the FB4050L?
The standard line and load side lug terminals accept 14 AWG through 1/0 AWG copper or aluminum conductors.
What does the "L" suffix in the FB4050L catalog number indicate?
In Eaton and Cutler-Hammer F-Frame nomenclature, the "L" suffix indicates that the circuit breaker is supplied with both line and load side lug terminals installed.
Is the FB4050L rated for use in direct current (DC) systems?
Yes, this breaker is rated for DC applications up to 250VDC with a maximum interrupting capacity of 10kA.
Does the FB4050L plug into the panelboard bus?
No, this is a unit mount circuit breaker. It does not plug in and must be hardwired or bolted directly to the chassis or mounting pan.
Are the trip settings adjustable on the FB4050L?
No, this breaker features a fixed thermal and fixed magnetic trip unit. It provides standard Long-Time and Instantaneous (LI) protection without adjustable dials.
Is the FB4050L considered a legacy frame?
Yes, the FB series is part of the legacy F-Frame molded case circuit breaker family originally manufactured by Westinghouse and Cutler-Hammer, which is now under the Eaton brand.
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Customers rate this product 5.0 out of 5 based on 2 reviews.