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Used Siemens Miniature Circuit Breakers (Mcb)

  • Siemens,5SY4105-7,1 Pole Circuit Breaker

    Siemens,5SY4105-7,1 Pole Circuit Breaker

    • Manufacturer: Siemens

    What's Included? See photos. We try our best to provide full details of each item and any included accessories, but if it's not shown in the photos then it will not be included with the item. 30-Day Easy Returns ...

    $8 USD
    Galion, OH
  • Siemens,5SX22 D16,Circuit Breaker

    Siemens,5SX22 D16,Circuit Breaker

    • Manufacturer: Siemens

    What's Included? See photos. We try our best to provide full details of each item and any included accessories, but if it's not shown in the photos then it will not be included with the item. 30-Day Easy Returns ...

    $12 USD
    Galion, OH
  • Trusted Seller
    Siemens Circuit Breaker, 5SY61, MCB

    Siemens Circuit Breaker, 5SY61, MCB C6

    • Manufacturer: Siemens

    Came from working unit 30 day warranty Wr30 Bin 4 Mpn: 5SY61 | Number of poles: 1 | Voltage rating: 277V

    $10 USD
    Muskegon, MI
  • Trusted Seller
    Siemens Circuit Breaker, 5SY61 MCB

    Siemens Circuit Breaker, 5SY61 MCB C 16

    • Manufacturer: Siemens

    Came from working unit 30 day warranty Wr30 Bin4 Mpn: 5SY61 | Number of poles: 1 | Voltage rating: 277V

    $15 USD
    Muskegon, MI
  • Siemens,5SY4 108-8,Miniature Circuit Breaker 1P

    Siemens,5SY4 108-8,Miniature Circuit Breaker 1P 230/400V

    • Manufacturer: Siemens

    New unused with original box NOS. Please see pictures for details and condition. You will receive what’s in the pictures. If we have multiples of the same item, the pictures may differ. Please review the pictures...

    $20 USD
    Galion, OH
  • Trusted Seller
    Siemens Circuit Breaker, 5SY61 MCB

    Siemens Circuit Breaker, 5SY61 MCB C10 5ST3010 AS

    • Manufacturer: Siemens

    Came from working unit 30 day warranty Wr30 Bin 4 Mpn: 5SY61 | Number of poles: 1 | Voltage rating: 277V

    $10 USD
    Muskegon, MI
  • Trusted Seller
    Box of 4 Siemens 5SX2

    Box of 4 Siemens 5SX2 325-7 Miniature Circuit Breaker 25A 400VAC 3 Pole New NIB

    • Manufacturer: Siemens

    This is a new surplus Siemens Miniature Circuit Breaker. Save thousands and buy from Green Industrial today!

    $300 USD
    Belgium, WI
  • Trusted Seller
    SIEMENS 5SY61MCB C4 CIRCUIT BREAKER

    SIEMENS 5SY61MCB C4 CIRCUIT BREAKER W/ AS AUX SWITCH ($12 OBO)

    • Manufacturer: Siemens

    “USED, EXCELLENT” SIEMENS 5SY61MCB C4 CIRCUIT BREAKER W/ AS AUX SWITCH 4 AMP 1 POLE 230/400 VAC 6 KA C-CURVE ***Local deliveries available, simply message us before purchasing so we can properly adjust the listin...

    $12 USD
    Waukesha, WI
  • Trusted Seller
    SIEMENS 5SY61MCB C6 CIRCUIT BREAKER

    SIEMENS 5SY61MCB C6 CIRCUIT BREAKER W/ AS AUX SWITCH ($12 OBO)

    • Manufacturer: Siemens

    “USED, EXCELLENT” SIEMENS 5SY61MCB C6 CIRCUIT BREAKER W/ AS AUX SWITCH 1 POLE 6 AMP 230/400 VAC C-CURVE 6 KA ***Local deliveries available, simply message us before purchasing so we can properly adjust the listin...

    $12 USD
    Waukesha, WI
  • Trusted Seller
    SIEMENS 5SY61MCB C10 CIRCUIT BREAKER

    SIEMENS 5SY61MCB C10 CIRCUIT BREAKER W/ AS AUX SWITCH ($12 OBO)

    • Manufacturer: Siemens

    “USED, EXCELLENT” SIEMENS 5SY61 MCB C10 CIRCUIT BREAKER W/ AS AUX SWITCH 10 AMP 1 POLE 230/400 VAC C-CURVE 6KA ***Local deliveries available, simply message us before purchasing so we can properly adjust the list...

    $12 USD
    Waukesha, WI
  • Siemens 5SY41 MCB A6 Circuit

    Siemens 5SY41 MCB A6 Circuit Breaker w/5ST3010AS Auxiliary Circuit. 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 5SY4350-5 MCB A50 Circuit

    Siemens 5SY4350-5 MCB A50 Circuit Breaker. 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, ...

    $45 USD
    Duncan, SC
  • Siemens 5SY4302-7 Miniature Circuit Breaker,

    Siemens 5SY4302-7 Miniature Circuit Breaker, 400V. 4D-48

    • 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, ...

    $59 USD
    Duncan, SC
  • Siemens 5SY4330-7 Miniature Circuit Breaker,

    Siemens 5SY4330-7 Miniature Circuit Breaker, 400V. 4D-48

    • 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, ...

    $178 USD
    Duncan, SC
  • Siemens 5SY4106-7 MCB C6 Miniature

    Siemens 5SY4106-7 MCB C6 Miniature Circuit Breaker. 4D-47

    • 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
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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.