MCBs

MCBs, or miniature circuit breakers, are a type of switch used to automatically turn off electrical circuits during abnormal conditions. Often replacing fuses in low voltage electrical circuits as they are more reliable, more sensitive and are resettable. Miniature circuit breakers are designed to protect electric circuits from overcurrent.

Typically mounted on DIN Rail and used in consumer units and distribution boards in a range of industrial, commercial, and domestic applications. You can learn more about MCBs in our complete MCB guide.

RS Components offer a comprehensive selection of high-quality Miniature Circuit Breakers from industry-leading brands including ABB, Siemens, Schneider Electric, Eaton, Rockwell Automation and Lovato.

How does a miniature circuit breaker work?

When continuous overcurrent flows through an MCB, a bimetallic strip is heated and causes it to bend. This bending of the bimetallic strip releases a mechanical latch opening the contacts and turning off the MCB, thereby stopping the current to flow in the circuit.

To restart the flow of current the MCB must be manually turned on. This mechanism protects the MCB from faults arising due to overcurrent or overload and is intended to prevent the accidental overloading of the cable in a no-fault situation.

The speed of the MCB tripping will vary with the degree of the overload. This is usually achieved using a thermal device in the MCB.

The second characteristic is the magnetic fault protection, which is intended to operate when the fault reaches a predetermined level and to trip the MCB within one-tenth of a second. The level of this magnetic trip gives the MCB its type characteristic.

What are the different types of circuit breakers?

There are three common types of electrical circuit protection in residential, commercial, and industrial applications. The use is classified by a curve type, which determines the tripping characteristics of the MCB:

Curve B - trips between 3 and 5 times the load current

Type B will trip instantly at a rate of three to five times its rated current. These are normally used for resistive or small inductive loads where switching surges are very small. Therefore, these are suitable for residential or light commercial installations.

Curve C - trips between 5 and 10 times the full load current

Type C will trip instantly at a rate of five to ten times its rated current. These are normally used for high inductive loads where switching surges are high such as small motors and fluorescent lighting. In such cases, type C MCBs are preferred to handle higher values of short circuit currents

Curve D - trips between 10 and 20 times the full load current

Type D will trip instantly at a rate of ten to twenty-five times its rated current. These are normally used for very high inductive loads where high inrush current is very frequent. Applications include x-ray machines, UPS systems, industrial welding equipment, large winding motors, etc.


...
Read more Read less

Filter

Visar 1 - 20 av 5284 produkter
Resultat per sida
Beskrivning Pris Number of Poles Current Rating Series Tripping Characteristics Rated AC Voltage Breaking Capacity at Maximum Voltage Rating Rated DC Voltage Model Number Range Breaking Capacity Circuit Breaker Type Mounting Style Length Width
RS-artikelnummer 521-4989
Tillv. art.nr5SY6105-7
VarumärkeSiemens
357,24 kr
Each
Enheter
1P 500mA 5SY6 Type C 230 V, 400V 6 kA - - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 521-4939
Tillv. art.nr5SY6102-7
VarumärkeSiemens
357,24 kr
Each
Enheter
1P 2A 5SY6 Type C 230 V, 400V 6 kA - - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 864-4330
Tillv. art.nr242212 PLSM-C63-MW
VarumärkeEaton
198,06 kr
Each
Enheter
1P 63A PLSM Type C - 10 kA 48V - xPole - MCB DIN Rail Mount 17.5mm 80mm
RS-artikelnummer 772-1372
Tillv. art.nr5SY4310-7
VarumärkeSiemens
1 091,99 kr
Each
Enheter
3P 10A 5SY4 Type C 400V 10 kA - - Sentron - MCB DIN Rail Mount 89.8mm 53mm
RS-artikelnummer 535-4144
Tillv. art.nr2CDS271001R0104 S201M-C10
VarumärkeABB
276,38 kr
Each
Enheter
1P 10A S200M Type C 253V 10 kA 72V S201M-C10 System Pro M Compact - MCB DIN Rail Mount 88mm 17.5mm
RS-artikelnummer 772-1347
Tillv. art.nr5SY4232-7
VarumärkeSiemens
1 194,37 kr
Each
Enheter
2P 32A 5SY4 Type C 400V 10 kA - - Sentron - MCB DIN Rail Mount 90mm 36mm
RS-artikelnummer 622-0014
Tillv. art.nr5SY4102-7
VarumärkeSiemens
366,84 kr
Each
Enheter
1P 2A 5SY4 Type C 230 V, 400V 10 kA - - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 847-3639
Tillv. art.nr102223 FAZ-D5/2-RT
VarumärkeEaton
1 329,16 kr
Each
Enheter
2P 5A FAZ Type D 240 → 415V 10 kA - - xEffect - MCB DIN Rail Mount 35.4mm 105mm
RS-artikelnummer 489-6530
Tillv. art.nr5SY6106-6
VarumärkeSiemens
188,75 kr
Each
Enheter
1P 6A 5SY6 Type B 230 V, 400V 6 kA - - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 521-4951
Tillv. art.nr5SY6104-7
VarumärkeSiemens
357,24 kr
Each
Enheter
1P 4A 5SY6 Type C 230 V, 400V 6 kA - - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 825-5586
Tillv. art.nrP1MB1PC04
VarumärkeLovato
167,10 kr
Each
Enheter
1P 4A P1MB Type C 230V 10 kA 60V - ModuLo - MCB DIN Rail Mount 86.5mm 18mm
RS-artikelnummer 535-4267
Tillv. art.nr2CDS273001R0104 S203M-C10
VarumärkeABB
1 006,47 kr
Each
Enheter
3P 10A S200M Type C 440V 10 kA - S203M-C10 System Pro M Compact - MCB DIN Rail Mount - -
RS-artikelnummer 488-7457
Tillv. art.nr2CDS251001R0065 - S201B6
VarumärkeABB
96,04 kr
Each
Enheter
1P 6A S200 Type B 253V 6 kA 72V S201-B6 System Pro M Compact - MCB DIN Rail Mount 88mm 17.5mm
RS-artikelnummer 798-2205
Tillv. art.nrEUB16B
VarumärkeEuropa
41,83 kr
Each
Enheter
1P 6A EUB Type B 230 V ac, 240 V ac - - EUB16B EUB1 - MCB - - -
RS-artikelnummer 539-8346
Tillv. art.nr2CDS213001R0104 SH203-C10
VarumärkeABB
413,92 kr
Each
Enheter
3P 10A SH200 Type C 440V 6 kA - SH203-C10 Compact Home - MCB DIN Rail Mount 85mm 52.5mm
RS-artikelnummer 489-6625
Tillv. art.nr5SY6106-7
VarumärkeSiemens
357,24 kr
Each
Enheter
1P 6A 5SY6 Type C 230 V, 400V 6 kA 72V - Sentron - MCB DIN Rail Mount 89.8mm 17.5mm
RS-artikelnummer 535-4138
Tillv. art.nr2CDS271001R0064 S201M-C6
VarumärkeABB
320,53 kr
Each
Enheter
1P 6A S200M Type C 253V 10 kA 72V S201M-C6 System Pro M Compact - MCB DIN Rail Mount 88mm 17.5mm
RS-artikelnummer 539-8217
Tillv. art.nr2CDS211001R0104 SH201-C10
VarumärkeABB
109,06 kr
Each
Enheter
1P 10A SH200 Type C 440V 6 kA 60V SH201-C10 Compact Home - MCB DIN Rail Mount 85mm 17.5mm
RS-artikelnummer 488-7110
Tillv. art.nr2CDS251001R0105 - S201B10
VarumärkeABB
84,87 kr
Each
Enheter
1P 10A S200 Type B 253V 6 kA 72V S201B10 System Pro M Compact - MCB DIN Rail Mount 88mm 17.5mm
RS-artikelnummer 535-4100
Tillv. art.nr2CDS271001R0024 S201M-C2
VarumärkeABB
321,62 kr
Each
Enheter
1P 2A S200M Type C 253V 10 kA 72V S201M-C2 System Pro M Compact - MCB DIN Rail Mount 88mm 17.5mm