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Used Miniature Circuit Breakers (Mcb)

  • Siemens 5SY63 MCB D32 Circuit

    Siemens 5SY63 MCB D32 Circuit Breaker. 4C-21

    • Manufacturer: Siemens

    Siemens 5SY63 MCB D32 Circuit Breaker. 4C-21 We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, PLC's, Sensors, Process Controls and Timers. Palmet...

    $35 USD
    Duncan, SC
  • Trusted Seller
    Cutler-Hammer WMS2C60 Miniature Circuit Breaker,

    Cutler-Hammer WMS2C60 Miniature Circuit Breaker, 2-Pole, 60A, 415V

    • Manufacturer: Cutler-Hammer

    PLEASE REVIEW: We would ask that potential buyers please view the photographs carefully, and understand what you are buying. All questions should be submitted PRIOR to making your purchase. *Your purchase include...

    $25 USD
    Suwanee, GA
  • Siemens 5SY63 MCB D25 Circuit

    Siemens 5SY63 MCB D25 Circuit Breaker. 4C-19

    • Manufacturer: Siemens

    Siemens 5SY63 MCB D25 Circuit Breaker. 4C-19 We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, PLC's, Sensors, Process Controls and Timers. Palmet...

    $28 USD
    Duncan, SC
  • Siemens 5SY63 MCB D4 Circuit

    Siemens 5SY63 MCB D4 Circuit Breaker. 4C-17

    • Manufacturer: Siemens

    Siemens 5SY63 MCB D4 Circuit Breaker. 4C-17 We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, PLC's, Sensors, Process Controls and Timers. Palmetto A...

    $48 USD
    Duncan, SC
  • Trusted Seller
    Eaton FAZ–C6/1–SP Miniature Circuit Breaker

    Eaton FAZ–C6/1–SP Miniature Circuit Breaker 6A Single Pole *FACTORY SEALED*

    • Manufacturer: Eaton

    PLEASE REVIEW: We would ask that potential buyers please view the photographs carefully, and understand what you are buying. All questions should be submitted prior to your purchase. *Your purchase includes a 30 ...

    $22 USD
    Suwanee, GA
  • Siemens 5SY63 MCB D32 3-Pole

    Siemens 5SY63 MCB D32 3-Pole Circuit Breaker. 4C-20

    • Manufacturer: Siemens

    Siemens 5SY63 MCB D32 3-Pole Circuit Breaker. B4C-20 We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, PLC's, Sensors, Process Controls and Timer...

    $34 USD
    Duncan, SC
  • Trusted Seller
    Eaton FAZ-C5/2-NA 2 Pole Circuit

    Eaton FAZ-C5/2-NA 2 Pole Circuit Breaker

    • Manufacturer: Eaton

    Suwanee, GA
  • Siemens 5SY4302-7 MCB C2 Circuit

    Siemens 5SY4302-7 MCB C2 Circuit Breaker, 400V. 4B-51

    • Manufacturer: Siemens

    Items are spares/engineering demo hookups that were pulled from an industrial working environment. We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, ...

    $23 USD
    Duncan, SC
  • SIEMENS 5SY4303-7 MCB C3 Circuit

    SIEMENS 5SY4303-7 MCB C3 Circuit Breaker, 400V. 4B-51

    • Manufacturer: Siemens

    Items are spares/engineering demo hookups that were pulled from an industrial working environment. We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, ...

    $27 USD
    Duncan, SC
  • Siemens 5SY41 MCB A2 Circuit

    Siemens 5SY41 MCB A2 Circuit Breaker w/5ST3010 AS Auxiliary Switch. 4B-51

    • Manufacturer: Siemens

    Items are spares/engineering demo hookups that were pulled from an industrial working environment. We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, ...

    $23 USD
    Duncan, SC
  • GE EP60 UL Series Miniature

    GE EP60 UL Series Miniature Circuit Breaker EP61ULC03. Loc 4E-2

    • Manufacturer: GE

    GE EP60 UL Series Miniature Circuit Breaker EP61ULC03. Loc. 4E-2 New no box maintenance room spares and/or new liquidated machine take offs. May have minor scuffs or scratches when they were taken from storage. H...

    $39 USD
    Duncan, SC
  • ABB S201M-C6DC Miniature Circuit Breaker,

    ABB S201M-C6DC Miniature Circuit Breaker, 6A 220V. 4D-36

    • Manufacturer: ABB

    Items are spares/engineering demo hookups that were pulled from an industrial working environment. We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, ...

    $23 USD
    Duncan, SC
  • Trusted Seller
    Eaton FAZ-C10/3-NA Miniature Circuit Breaker,

    Eaton FAZ-C10/3-NA Miniature Circuit Breaker, 10 Amp, 3 Pole

    • Manufacturer: Eaton

    $65 USD
    Suwanee, GA
  • Trusted Seller
    EATON FAZ-D10/2RT BREAKER - BRAND

    EATON FAZ-D10/2RT BREAKER - BRAND NEW IN BOX ($16 OBO)

    • Manufacturer: Eaton

    EATON FAZ-D10/2-RT -BRAND NEW IN BOX- WILL DO DISCOUNTS ON MULTIPLE! MINIATURE CIRCUIT BREAKER 2 POLE 10 AMP 15 KA 480Y/277 VAC ***Local deliveries available, simply message us before purchasing so we can properl...

    $14 USD
    Waukesha, WI
  • SIEMENS 5SY43 MCB C3 CIRCUIT

    SIEMENS 5SY43 MCB C3 CIRCUIT BREAKER, 3 POLE, 400V. 4B-51

    • Manufacturer: Siemens

    Items are spares/engineering demo hookups that were pulled from an industrial working environment. We repair all types of industrial automation including AC Servo Drives, Servo Motors, Operator Interface Panels, ...

    $23 USD
    Duncan, SC
34567

Overview

Miniature circuit breakers (MCBs) are compact protective switches that interrupt electrical flow in low‑voltage circuits when overloads or short circuits occur. Widely used in residential, commercial and light industrial panels, they offer resettable protection and come in single‑ to multi‑pole versions, various current ratings, breaking capacities and trip curves. MCBs typically mount on DIN rails and use thermal‑magnetic mechanisms; select units that match local standards, busbar size and application requirements.

FAQ

What should I check when buying an MCB?

Verify the nominal current (In), breaking capacity (kA), trip curve (B, C, D), number of poles, mounting type (DIN rail), and compliance with local standards (IEC/UL). Check physical condition, brand reputation and whether spare parts or datasheets are available.

How should MCBs be packed and shipped safely?

Ship in original or padded boxes to protect terminals and housing. Secure against moisture and vibration, label fragile electrical components, and use a carrier familiar with electrical goods. Include compliance certificates for customs if shipping internationally.

What routine maintenance or testing do MCBs need?

Perform visual inspections, tighten terminal connections to torque specs, cycle switches periodically, and conduct insulation and trip tests with appropriate equipment. Replace units showing overheating, physical damage, or inconsistent trips.