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MCBs - Miniature Circuit Breakers

MCBs (Miniature Circuit Breakers)

What is an MCB?

MCB stands for Miniature Circuit Breaker. 

It's a small device designed to interrupt electrical flow when it detects abnormal conditions such as overload or short circuits. 

Essentially, it acts as a safety switch – protecting your electrical circuits and preventing potential hazards like fire or equipment damage.

How Do MCBs Work?

MCBs work by monitoring the flow of electricity through a circuit. 

When the current exceeds the MCB's rated capacity, or there's a short circuit, it trips - cutting off the power supply and preventing further damage.

Can I Change an MCB Myself?

Yes, MCBs are designed for easy installation and replacement. 

However, you’ll need to follow proper safety procedures and will need the knowledge and skills to handle electrical work safely. 

It's always best to consult a qualified electrician if you're unsure.

What Size MCB for Sockets?

The MCB's size depends on the electrical circuit's rating and the appliances connected to it. 

A 32A or 40A MCB is typically suitable for socket outlets commonly used in homes. 

However, you should consult electrical regulations and guidelines to pick the right size for your specific application.

Can MCBs Be Used for DC?

Yes, MCBs can be used for both AC (alternating current) and DC (direct current) circuits. 

However, you should choose MCBs specifically rated for DC applications to ensure you get the right protection and performance.

What Are the Types of MCB?

Various types of MCBs are available, including Type B, Type C, and Type D, each designed to trip at different levels of overload or short circuit currents.

What is the Tripping Mechanism of an MCB?

The tripping mechanism of an MCB is typically based on either thermal or magnetic principles. 

Thermal MCBs respond to the heat generated by overcurrent, while magnetic MCBs detect sudden surges in current. 

Some MCBs feature both mechanisms for better protection.

Where Are MCBs Installed?

MCBs are installed in electrical distribution boards, consumer units, or fuse boxes to protect individual circuits or groups of circuits within a building. 

They are commonly found in residential, commercial, and industrial settings.

Can I Reset an MCB?

Yes, most MCBs feature a reset function that allows you to restore power to the circuit after it has tripped. 

Simply switch the MCB back to the "on" position after fixing the cause of the trip.

Invest in quality MCBs today to ensure the safety and reliability of your electrical installations. 

Browse our selection of MCBs to find the perfect solution for your needs!

Filters

  • £14.39 - £14.39
    £14.39 inc VAT
    £14.39 - £14.39
    £14.39 inc VAT
    £11.99 ex VAT

    Siemens 5SY4116-5 Miniature Circuit Breaker 230/400 V 10kA, 1-Pole, A, 16A, D=70 Mm

    Miniature circuit breaker 230/400 V 10kA, 1-pole, A, 16A, D=70 mm The miniature circuit breaker is the fuse for short-circuit protection. The minia...

    View full details
    £14.39 - £14.39
    £14.39 inc VAT
    £14.39 - £14.39
    £14.39 inc VAT
    £11.99 ex VAT
  • £10.56 - £10.56
    £10.56 inc VAT
    £10.56 - £10.56
    £10.56 inc VAT
    £8.80 ex VAT

    Siemens 5SY4132-7 MCB SP Type C 32A 10Ka

    Miniature circuit breaker 230/400 V 10kA, 1-pole, C, 32 A, D=70 mm The miniature circuit breaker is the fuse for short-circuit protection. The mini...

    View full details
    £10.56 - £10.56
    £10.56 inc VAT
    £10.56 - £10.56
    £10.56 inc VAT
    £8.80 ex VAT
  • £9.07 - £9.07
    £9.07 inc VAT
    £9.07 - £9.07
    £9.07 inc VAT
    £7.56 ex VAT

    Siemens 5SY4140-6 MCB SP Type B 40A 10Ka

    Miniature circuit breaker 230/400 V 10kA, 1-pole, B, 40A, D=70 mm The miniature circuit breaker is the fuse for short-circuit protection. The minia...

    View full details
    £9.07 - £9.07
    £9.07 inc VAT
    £9.07 - £9.07
    £9.07 inc VAT
    £7.56 ex VAT
  • £11.23 - £11.23
    £11.23 inc VAT
    £11.23 - £11.23
    £11.23 inc VAT
    £9.36 ex VAT

    Siemens 5SY7132-6 MCB SP Type B 32A 16Ka

    Siemens - Modular Instl Devices 5SY7132-6 Stratum MCB SP Type B 32A 16kA • EAN - 4001869190495 • UPC - Not available • Commodity Code - 85362010 • ...

    View full details
    £11.23 - £11.23
    £11.23 inc VAT
    £11.23 - £11.23
    £11.23 inc VAT
    £9.36 ex VAT
  • £28.74 - £28.74
    £28.74 inc VAT
    £28.74 - £28.74
    £28.74 inc VAT
    £23.95 ex VAT

    Siemens 5SY4201-8 MCB DP Type D 1A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £28.74 - £28.74
    £28.74 inc VAT
    £28.74 - £28.74
    £28.74 inc VAT
    £23.95 ex VAT
  • £9.83 - £9.83
    £9.83 inc VAT
    £9.83 - £9.83
    £9.83 inc VAT
    £8.19 ex VAT

    Siemens 5SY4150-8 MCB SP Type D 50A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £9.83 - £9.83
    £9.83 inc VAT
    £9.83 - £9.83
    £9.83 inc VAT
    £8.19 ex VAT
  • £4.86 - £4.86
    £4.86 inc VAT
    £4.86 - £4.86
    £4.86 inc VAT
    £4.05 ex VAT

    Siemens 5SL4150-6 MCB 230/400 V 1

    Miniature circuit breaker 230/400 V 10kA, 1-pole, B, 50 A • CIRCUIT BREAKER 10KA 1POLE B50

    £4.86 - £4.86
    £4.86 inc VAT
    £4.86 - £4.86
    £4.86 inc VAT
    £4.05 ex VAT
  • £9.83 - £9.83
    £9.83 inc VAT
    £9.83 - £9.83
    £9.83 inc VAT
    £8.19 ex VAT

    Siemens 5SY4104-8 MCB SP Type D 4A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £9.83 - £9.83
    £9.83 inc VAT
    £9.83 - £9.83
    £9.83 inc VAT
    £8.19 ex VAT
  • £18.40 - £18.40
    £18.40 inc VAT
    £18.40 - £18.40
    £18.40 inc VAT
    £15.33 ex VAT

    Siemens 5SL4320-6 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, B, 20 A • CIRCUIT BREAKER 10KA 3POLE B20

    £18.40 - £18.40
    £18.40 inc VAT
    £18.40 - £18.40
    £18.40 inc VAT
    £15.33 ex VAT
  • £30.58 - £30.58
    £30.58 inc VAT
    £30.58 - £30.58
    £30.58 inc VAT
    £25.48 ex VAT

    Siemens 5SY6313-7 MCB Type C TP 6Ka 13A 400V AC

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £30.58 - £30.58
    £30.58 inc VAT
    £30.58 - £30.58
    £30.58 inc VAT
    £25.48 ex VAT
  • £4.53 - £4.53
    £4.53 inc VAT
    £4.53 - £4.53
    £4.53 inc VAT
    £3.78 ex VAT

    Siemens 5SL4120-8 MCB 230/400 V 1

    Miniature circuit breaker 230/400 V 10kA, 1-pole, D, 20 A • Miniature circuit breaker 230/400 V 10 kA, 1-pole, D, 20 A

    £4.53 - £4.53
    £4.53 inc VAT
    £4.53 - £4.53
    £4.53 inc VAT
    £3.78 ex VAT
  • £20.30 - £20.30
    £20.30 inc VAT
    £20.30 - £20.30
    £20.30 inc VAT
    £16.92 ex VAT

    Siemens 5SL4363-8 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, D, 63 A • CIRCUIT BREAKER 10KA 3POLE D63

    £20.30 - £20.30
    £20.30 inc VAT
    £20.30 - £20.30
    £20.30 inc VAT
    £16.92 ex VAT
  • £17.27 - £17.27
    £17.27 inc VAT
    £17.27 - £17.27
    £17.27 inc VAT
    £14.39 ex VAT

    Siemens 5SL4308-6 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, B, 8A • CIRCUIT BREAKER 10KA 3POLE B8

    £17.27 - £17.27
    £17.27 inc VAT
    £17.27 - £17.27
    £17.27 inc VAT
    £14.39 ex VAT
  • £17.95 - £17.95
    £17.95 inc VAT
    £17.95 - £17.95
    £17.95 inc VAT
    £14.96 ex VAT

    Siemens 5SL4325-8 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, D, 25A • CIRCUIT BREAKER 10KA 3POLE D25

    £17.95 - £17.95
    £17.95 inc VAT
    £17.95 - £17.95
    £17.95 inc VAT
    £14.96 ex VAT
  • £23.40 - £23.40
    £23.40 inc VAT
    £23.40 - £23.40
    £23.40 inc VAT
    £19.50 ex VAT

    Siemens 5SL4216-7 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 2-pole, C, 16A • CIRCUIT BREAKER 10KA 2POLE C16

    £23.40 - £23.40
    £23.40 inc VAT
    £23.40 - £23.40
    £23.40 inc VAT
    £19.50 ex VAT
  • £24.74 - £24.74
    £24.74 inc VAT
    £24.74 - £24.74
    £24.74 inc VAT
    £20.62 ex VAT

    Siemens 5SY4220-8 MCB DP Type D 20A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £24.74 - £24.74
    £24.74 inc VAT
    £24.74 - £24.74
    £24.74 inc VAT
    £20.62 ex VAT
  • £27.24 - £27.24
    £27.24 inc VAT
    £27.24 - £27.24
    £27.24 inc VAT
    £22.70 ex VAT

    Siemens 5SY4206-8 MCB DP Type D 6A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £27.24 - £27.24
    £27.24 inc VAT
    £27.24 - £27.24
    £27.24 inc VAT
    £22.70 ex VAT
  • £10.03 - £10.03
    £10.03 inc VAT
    £10.03 - £10.03
    £10.03 inc VAT
    £8.36 ex VAT

    Siemens 5SY4103-8 MCB SP Type D 3A 10Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £10.03 - £10.03
    £10.03 inc VAT
    £10.03 - £10.03
    £10.03 inc VAT
    £8.36 ex VAT
  • £4.53 - £4.53
    £4.53 inc VAT
    £4.53 - £4.53
    £4.53 inc VAT
    £3.78 ex VAT

    Siemens 5SL4132-8 MCB 230/ 400V 1

    Miniature circuit breaker 230/400 V 10kA, 1-pole, D, 32 A • Miniature circuit breaker 230/400 V 10 kA, 1-pole, D, 32 A

    £4.53 - £4.53
    £4.53 inc VAT
    £4.53 - £4.53
    £4.53 inc VAT
    £3.78 ex VAT
  • £17.27 - £17.27
    £17.27 inc VAT
    £17.27 - £17.27
    £17.27 inc VAT
    £14.39 ex VAT

    Siemens 5SL4313-6 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, B, 13A • CIRCUIT BREAKER 10KA 3POLE B13

    £17.27 - £17.27
    £17.27 inc VAT
    £17.27 - £17.27
    £17.27 inc VAT
    £14.39 ex VAT
  • £8.48 - £8.48
    £8.48 inc VAT
    £8.48 - £8.48
    £8.48 inc VAT
    £7.07 ex VAT

    Siemens 5SY6163-7 MCB SP C Trip 63A 6Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £8.48 - £8.48
    £8.48 inc VAT
    £8.48 - £8.48
    £8.48 inc VAT
    £7.07 ex VAT
  • £18.40 - £18.40
    £18.40 inc VAT
    £18.40 - £18.40
    £18.40 inc VAT
    £15.33 ex VAT

    Siemens 5SL4325-6 MCB 400V 10Ka

    Miniature circuit breaker 400 V 10kA, 3-pole, B, 25A • CIRCUIT BREAKER 10KA 3POLE B25

    £18.40 - £18.40
    £18.40 inc VAT
    £18.40 - £18.40
    £18.40 inc VAT
    £15.33 ex VAT
  • £19.95 - £19.95
    £19.95 inc VAT
    £19.95 - £19.95
    £19.95 inc VAT
    £16.63 ex VAT

    Siemens 5SY6216-7 MCB DP C Trip 16A 6Ka

    Siemens miniature circuit breaker is used to protect systems and installations in buildings and for industrial applications. The devices are approv...

    View full details
    £19.95 - £19.95
    £19.95 inc VAT
    £19.95 - £19.95
    £19.95 inc VAT
    £16.63 ex VAT

MCBs (Miniature Circuit Breakers)

What is an MCB?

MCB stands for Miniature Circuit Breaker. 

It's a small device designed to interrupt electrical flow when it detects abnormal conditions such as overload or short circuits. 

Essentially, it acts as a safety switch – protecting your electrical circuits and preventing potential hazards like fire or equipment damage.

How Do MCBs Work?

MCBs work by monitoring the flow of electricity through a circuit. 

When the current exceeds the MCB's rated capacity, or there's a short circuit, it trips - cutting off the power supply and preventing further damage.

Can I Change an MCB Myself?

Yes, MCBs are designed for easy installation and replacement. 

However, you’ll need to follow proper safety procedures and will need the knowledge and skills to handle electrical work safely. 

It's always best to consult a qualified electrician if you're unsure.

What Size MCB for Sockets?

The MCB's size depends on the electrical circuit's rating and the appliances connected to it. 

A 32A or 40A MCB is typically suitable for socket outlets commonly used in homes. 

However, you should consult electrical regulations and guidelines to pick the right size for your specific application.

Can MCBs Be Used for DC?

Yes, MCBs can be used for both AC (alternating current) and DC (direct current) circuits. 

However, you should choose MCBs specifically rated for DC applications to ensure you get the right protection and performance.

What Are the Types of MCB?

Various types of MCBs are available, including Type B, Type C, and Type D, each designed to trip at different levels of overload or short circuit currents.

What is the Tripping Mechanism of an MCB?

The tripping mechanism of an MCB is typically based on either thermal or magnetic principles. 

Thermal MCBs respond to the heat generated by overcurrent, while magnetic MCBs detect sudden surges in current. 

Some MCBs feature both mechanisms for better protection.

Where Are MCBs Installed?

MCBs are installed in electrical distribution boards, consumer units, or fuse boxes to protect individual circuits or groups of circuits within a building. 

They are commonly found in residential, commercial, and industrial settings.

Can I Reset an MCB?

Yes, most MCBs feature a reset function that allows you to restore power to the circuit after it has tripped. 

Simply switch the MCB back to the "on" position after fixing the cause of the trip.

Invest in quality MCBs today to ensure the safety and reliability of your electrical installations. 

Browse our selection of MCBs to find the perfect solution for your needs!

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