Mini Circuit Breakers

Miniature circuit breakers (MCBs) are compact, resettable protection devices used to safeguard electrical circuits from overcurrent and short-circuit conditions. Commonly installed in distribution panels and control enclosures, MCBs protect wiring, connected equipment, and control circuits by automatically interrupting current flow when unsafe conditions occur. RSP Supply offers a full range of miniature circuit breakers suitable for residential, commercial, and industrial applications.

MCBs are available in single-pole, double-pole, and four-pole configurations, allowing protection for both single-phase and three-phase electrical systems. Different trip curve types are designed to match specific application needs. Type B breakers are typically used in residential environments where lower inrush currents are expected. Type C and Type D breakers are more common in commercial and industrial installations, where higher inrush currents from motors, transformers, or power supplies are present.

Unlike fuses, miniature circuit breakers do not need to be replaced after a fault condition. Once the cause of the trip is resolved, the breaker can be reset, restoring circuit protection without additional components. Many DIN rail–mounted MCBs are designed with robust housings that provide resistance to shock and vibration, ensuring dependable operation in demanding industrial environments.

Found 498 items
Normally In Stock
Schneider Electric M9F22432 Four Pole 32 Amp Breaker
Free U.S Ground shipping
$420.41
$350.34
Normally In Stock
ABB S804U-K50 Mini CB - 50 Amp, 4P
Free U.S Ground shipping
$800.18
$666.82
Normally In Stock
Schneider Electric M9F22413 Four Pole 13 Amp Breaker
Free U.S Ground shipping
$420.41
$350.34
Normally In Stock
Schneider Electric M9F22450 Four Pole 50 Amp Breaker
Free U.S Ground shipping
$460.51
$383.76
Normally In Stock
Eaton FAZ-B50/4 Mini CB - 50 Amp, Four Pole, 277 VAC, B Curve
Free U.S Ground shipping
$367.90
$306.58
Normally In Stock
Eaton FAZ-B6/4 Mini CB - 6 Amp, Four Pole, 277 VAC, B Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-B63/4 Mini CB - 63 Amp, Four Pole, 277 VAC, B Curve
Free U.S Ground shipping
$367.90
$306.58
Normally In Stock
Eaton FAZ-B8/4 Mini CB - 8 Amp, Four Pole, 277 VAC, B Curve
Free U.S Ground shipping
$286.33
$238.61
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Eaton FAZ-C1/4 Mini CB - 1 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$298.03
$248.36
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Eaton FAZ-C10/4 Mini CB - 10 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C13/4 Mini CB - 13 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C15/4 Mini CB - 15 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C16/4 Mini CB - 16 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C2/4 Mini CB - 2 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$298.03
$248.36
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Eaton FAZ-C20/4 Mini CB - 20 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C25/4 Mini CB - 25 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C3/4 Mini CB - 3 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-C32/4 Mini CB - 32 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C40/4 Mini CB - 40 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$299.47
$249.56
Normally In Stock
Eaton FAZ-C5/4 Mini CB - 5 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-C50/4 Mini CB - 50 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$367.90
$306.58
Normally In Stock
Eaton FAZ-C6/4 Mini CB - 6 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-C63/4 Mini CB - 63 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$367.90
$306.58
Normally In Stock
Eaton FAZ-C8/4 Mini CB - 8 Amp, Four Pole, 277 VAC, C Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D1/4 Mini CB - 1 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-D10/4 Mini CB - 10 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D13/4 Mini CB - 13 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D15/4 Mini CB - 15 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D16/4 Mini CB - 16 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D20/4 Mini CB - 20 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D25/4 Mini CB - 25 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D3/4 Mini CB - 3 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-D32/4 Mini CB - 32 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D4/4 Mini CB - 4 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-D40/4 Mini CB - 40 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$299.47
$249.56
Normally In Stock
Eaton FAZ-D5/4 Mini CB - 5 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$298.03
$248.36
Normally In Stock
Eaton FAZ-D6/4 Mini CB - 6 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-D8/4 Mini CB - 8 Amp, Four Pole, 277 VAC, D Curve
Free U.S Ground shipping
$286.33
$238.61
Normally In Stock
Eaton FAZ-K1/4 Mini CB - 1 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$371.71
$309.76
Normally In Stock
Eaton FAZ-K10/4 Mini CB - 10 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$286.56
$238.80
Normally In Stock
Eaton FAZ-K13/4 Mini CB - 13 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$286.56
$238.80
Normally In Stock
Eaton FAZ-K16/4 Mini CB - 16 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$286.56
$238.80
Normally In Stock
Eaton FAZ-K2/4 Mini CB - 2 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$371.71
$309.76
Normally In Stock
Eaton FAZ-K20/4 Mini CB - 20 Amp, Four Pole, 277 VAC, K Curve
Free U.S Ground shipping
$286.56
$238.80

FAQs

Q: What is a miniature circuit breaker used for?
Miniature circuit breakers provide branch circuit and short-circuit protection by automatically interrupting current when an overcurrent or fault condition is detected.

Q: How are MCBs different from fuses?
MCBs can be reset after tripping, while fuses must be replaced once they open. MCBs provide reusable, consistent protection for electrical circuits.

Q: What do B, C, and D trip curves mean?
Trip curves define how quickly a breaker responds to overcurrent. B curve breakers trip at lower inrush currents, C curve breakers handle moderate inrush currents, and D curve breakers are designed for high inrush current applications such as motors and transformers.

Q: Can miniature circuit breakers be used in industrial applications?
Yes, MCBs are commonly used in industrial control panels and distribution systems, especially when designed with high vibration resistance and appropriate trip curves.

Q: How do miniature circuit breakers trip during a fault?
MCBs use a bimetal strip for prolonged overcurrent protection and a magnetic solenoid for rapid response to short-circuit or high-current events.

Why Buy Mini Circuit Breakers from RSP Supply

RSP Supply offers a broad selection of miniature circuit breakers designed to meet the protection requirements of residential, commercial, and industrial electrical systems. Our product lineup includes multiple pole configurations and trip curves to match a wide range of applications. Customers rely on RSP Supply for dependable circuit protection components, technical expertise, and solutions that support safe and reliable electrical system operation.