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Eaton / Cutler-Hammer FB4100 Molded Case Circuit Breaker

  • 100A
  • 4 Pole
  • Bolt-On
Eaton / Cutler-Hammer FB4100
Molded Case Circuit Breaker
Brand Eaton / Cutler-Hammer
SKU FB4100
Select Item Condition
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  • 100A
  • 4 Pole
  • Bolt-On

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Eaton/Cutler-Hammer FB4100 4 Pole Circuit Breaker

Eaton / Cutler-Hammer FB4100 - 100A 4 Pole Molded Case Circuit Breaker

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$404.44 No Stock

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Description

Operating as a critical safety component, the Eaton FB4100 is a 100-amp, 4-pole molded case circuit breaker. It relies on fixed thermal and magnetic trip elements to provide reliable long-time and instantaneous fault protection. This legacy breaker features a bolt-on configuration for stable installation in Cutler-Hammer and Westinghouse Pow-R-Line C panelboards and MCCs. Facilities looking for current equivalents can cross-reference the FD4100. It offers 14kAIC at 480VAC and load side lugs.

Specifications

Key specifications
Brand Eaton / Cutler-Hammer
Part Number FB4100-R
Series FB
Amperage 100A
Poles 4
Mounting Style Bolt-On
Voltage 240VAC, 480VAC, 600VAC, 250VDC
Phase 3
AIC Rating 18kA @ 240VAC, 14kA @ 480VAC, 14kA @ 600VAC, 10kA @ 250VDC
Fit and installation
Terminal Type Lugs
For Use With Westinghouse / Cutler-Hammer Pow-R-Line C Panelboards, FDP Panelboards, Switchboards, Motor Control Centers
Wire Gauge 14-1/0 AWG (Cu/Al)
Max Wire 1/0 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Fixed Magnetic
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch
Accessories Load Side Lugs Included
Standards NEMA AB-1, UL 489, CSA C22.2 No. 5
Approval CSA, UL
Temp Rating 40C
Construction Features Non-Interchangeable Trip, Common Trip

Product FAQs

4 answers
Which panelboards are compatible with the FB4100 circuit breaker?

The FB4100 is an F-frame breaker designed for bolt-on installation in legacy and current Westinghouse or Cutler-Hammer distribution equipment, specifically Pow-R-Line C and FDP panelboards, as well as compatible switchboards and motor control centers.

Can the Eaton FB4100 replace older Westinghouse FB breakers?

Yes. Because Eaton acquired the Cutler-Hammer and Westinghouse distribution equipment lines, the FB4100 serves as a direct replacement for legacy Westinghouse and Cutler-Hammer FB-frame breakers with matching specifications.

What is the purpose of the fourth pole on this 3-phase breaker?

In a 3-phase, 4-wire system, the fourth pole is typically utilized to switch or isolate the neutral conductor. This is required in specific installations where complete isolation of all grounded and ungrounded conductors is necessary for safety or system design.

How does the LI thermal magnetic trip unit operate on the FB4100?

The LI designation indicates two forms of protection. It uses a fixed thermal element (Long-Time) that responds to gradual overloads by heating a bimetallic strip, and a fixed magnetic element (Instantaneous) that responds immediately to severe short circuits.

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Reviews

5.0
Rated 5.0 out of 5 stars
Based on 2 reviews
Total 5 star reviews: 2 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Rating
Ratings
2 reviews
  • SD
    Sal D.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer FB3125 - 125A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    4/16/26
    Breakers

    Really happy with the breakers and with the quickness they were delivered

  • CB
    Christopher B.
    Flag of United States
    Reviewing
    Eaton / Cutler-Hammer FB3015L - 15A 3 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    11/8/20
    AWESOME JOB

    Quick response and delivery. Exactly what I wanted.