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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!

  • Original price £17.95
    Original price £17.95 - Original price £17.95
    Original price £17.95
    Current price £3.68 inc VAT
    £3.68 - £3.68
    Current price £3.68 inc VAT
    £3.07 ex VAT

    Siemens 5SL4325-8 MCB 400V 10Ka

    Siemens
    In stock

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

    Original price £17.95
    Original price £17.95 - Original price £17.95
    Original price £17.95
    Current price £3.68 inc VAT
    £3.68 - £3.68
    Current price £3.68 inc VAT
    £3.07 ex VAT
    Save 79% Save %
  • Original price £23.40
    Original price £23.40 - Original price £23.40
    Original price £23.40
    Current price £8.19 inc VAT
    £8.19 - £8.19
    Current price £8.19 inc VAT
    £6.83 ex VAT

    Siemens 5SL4216-7 MCB 400V 10Ka

    Siemens
    In stock

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

    Original price £23.40
    Original price £23.40 - Original price £23.40
    Original price £23.40
    Current price £8.19 inc VAT
    £8.19 - £8.19
    Current price £8.19 inc VAT
    £6.83 ex VAT
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  • Original price £24.74
    Original price £24.74 - Original price £24.74
    Original price £24.74
    Current price £4.97 inc VAT
    £4.97 - £4.97
    Current price £4.97 inc VAT
    £4.14 ex VAT

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

    Siemens
    In stock

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

    View full details
    Original price £24.74
    Original price £24.74 - Original price £24.74
    Original price £24.74
    Current price £4.97 inc VAT
    £4.97 - £4.97
    Current price £4.97 inc VAT
    £4.14 ex VAT
    Save 80% Save %
  • Original price £27.24
    Original price £27.24 - Original price £27.24
    Original price £27.24
    Current price £5.49 inc VAT
    £5.49 - £5.49
    Current price £5.49 inc VAT
    £4.58 ex VAT

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

    Siemens
    In stock

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

    View full details
    Original price £27.24
    Original price £27.24 - Original price £27.24
    Original price £27.24
    Current price £5.49 inc VAT
    £5.49 - £5.49
    Current price £5.49 inc VAT
    £4.58 ex VAT
    Save 80% Save %
  • Original price £10.03
    Original price £10.03 - Original price £10.03
    Original price £10.03
    Current price £3.37 inc VAT
    £3.37 - £3.37
    Current price £3.37 inc VAT
    £2.81 ex VAT

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

    Siemens
    In stock

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

    View full details
    Original price £10.03
    Original price £10.03 - Original price £10.03
    Original price £10.03
    Current price £3.37 inc VAT
    £3.37 - £3.37
    Current price £3.37 inc VAT
    £2.81 ex VAT
    Save 66% Save %
  • Original price £4.53
    Original price £4.53 - Original price £4.53
    Original price £4.53
    Current price £1.04 inc VAT
    £1.04 - £1.04
    Current price £1.04 inc VAT
    £0.87 ex VAT

    Siemens 5SL4132-8 MCB 230/ 400V 1

    Siemens
    In stock

    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

    Original price £4.53
    Original price £4.53 - Original price £4.53
    Original price £4.53
    Current price £1.04 inc VAT
    £1.04 - £1.04
    Current price £1.04 inc VAT
    £0.87 ex VAT
    Save 77% Save %
  • Original price £17.27
    Original price £17.27 - Original price £17.27
    Original price £17.27
    Current price £3.54 inc VAT
    £3.54 - £3.54
    Current price £3.54 inc VAT
    £2.95 ex VAT

    Siemens 5SL4313-6 MCB 400V 10Ka

    Siemens
    In stock

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

    Original price £17.27
    Original price £17.27 - Original price £17.27
    Original price £17.27
    Current price £3.54 inc VAT
    £3.54 - £3.54
    Current price £3.54 inc VAT
    £2.95 ex VAT
    Save 80% Save %
  • Original price £8.48
    Original price £8.48 - Original price £8.48
    Original price £8.48
    Current price £1.71 inc VAT
    £1.71 - £1.71
    Current price £1.71 inc VAT
    £1.43 ex VAT

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

    Siemens
    In stock

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

    View full details
    Original price £8.48
    Original price £8.48 - Original price £8.48
    Original price £8.48
    Current price £1.71 inc VAT
    £1.71 - £1.71
    Current price £1.71 inc VAT
    £1.43 ex VAT
    Save 80% Save %
  • Original price £18.40
    Original price £18.40 - Original price £18.40
    Original price £18.40
    Current price £9.56 inc VAT
    £9.56 - £9.56
    Current price £9.56 inc VAT
    £7.97 ex VAT

    Siemens 5SL4325-6 MCB 400V 10Ka

    Siemens
    In stock

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

    Original price £18.40
    Original price £18.40 - Original price £18.40
    Original price £18.40
    Current price £9.56 inc VAT
    £9.56 - £9.56
    Current price £9.56 inc VAT
    £7.97 ex VAT
    Save 48% Save %
  • Original price £14.40
    Original price £14.40 - Original price £14.40
    Original price £14.40
    Current price £8.21 inc VAT
    £8.21 - £8.21
    Current price £8.21 inc VAT
    £6.84 ex VAT

    Wylex PSB310-B MCB B10 10kA 3P (3MW)

    Wylex
    In stock

    Wylex PSB310-B MCB TP Type B 10A 10kA • B curve trip characteristic (3-5In) • 10kA to BS EN 60898-1 (15kA to BS EN 60947-2) @ 415V AC • Triple pole...

    View full details
    Original price £14.40
    Original price £14.40 - Original price £14.40
    Original price £14.40
    Current price £8.21 inc VAT
    £8.21 - £8.21
    Current price £8.21 inc VAT
    £6.84 ex VAT
    Save 43% Save %
  • Original price £5.04 - Original price £5.04
    Original price
    £5.04 inc VAT
    £5.04 - £5.04
    Current price £5.04 inc VAT
    £4.20 ex VAT

    ABB S201-B50 MCB 1 Pole Type B 50A (2CDS251001R0505)

    ABB
    In stock

    ABB 2CDS251001R0505 1 Pole 50A Type B MCB with Failsafe bi-directional cylinder-lift screw terminal. This System pro M compact S201-B50 MCB is curr...

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    Original price £5.04 - Original price £5.04
    Original price
    £5.04 inc VAT
    £5.04 - £5.04
    Current price £5.04 inc VAT
    £4.20 ex VAT
  • Original price £0.00 - Original price £0.00
    Original price £0.00
    £6.42 inc VAT
    £6.42 - £6.42
    Current price £6.42 inc VAT
    £5.35 ex VAT

    ABB S201M-C50 MCB 1 Pole Type C 50A (2CDS271001R0504)

    ABB
    Low stock

    ABB 2CDS271001R0504 1 Pole 50A Type C MCB with Failsafe bi-directional cylinder-lift screw terminal. This System pro M compact S201M-C50 MCB is cur...

    View full details
    Original price £0.00 - Original price £0.00
    Original price £0.00
    £6.42 inc VAT
    £6.42 - £6.42
    Current price £6.42 inc VAT
    £5.35 ex VAT
  • Original price £6.86
    Original price £6.86 - Original price £6.86
    Original price £6.86
    Current price £5.35 inc VAT
    £5.35 - £5.35
    Current price £5.35 inc VAT
    £4.46 ex VAT

    Crabtree 70B/16 MCB B16 16kA 1P Type B 16A (1 Module Width)

    Crabtree
    In stock

    Crabtree - Wiring Accessories 70B/16 Polestar Compact MCB SP Type B 16A 16kA • B curve trip characteristic (3-5In) • 16kA to BS EN 60898-1 (15kA to...

    View full details
    Original price £6.86
    Original price £6.86 - Original price £6.86
    Original price £6.86
    Current price £5.35 inc VAT
    £5.35 - £5.35
    Current price £5.35 inc VAT
    £4.46 ex VAT
    Save 22% Save %
  • Original price £30.74
    Original price £30.74 - Original price £30.74
    Original price £30.74
    Current price £14.35 inc VAT
    £14.35 - £14.35
    Current price £14.35 inc VAT
    £11.96 ex VAT

    Dorman Smith K3PB10 MCB K Series Type B TP 10A 10KA

    Dorman Smith
    Low stock

    Dorman Smith Switchgear K3PB10 Loadlimiter 63 MCB K Series Type B TP 10A 10kA • Product: Circuit Breaker • Type: MCB • Pole Configuration: TP • Tri...

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    Original price £30.74
    Original price £30.74 - Original price £30.74
    Original price £30.74
    Current price £14.35 inc VAT
    £14.35 - £14.35
    Current price £14.35 inc VAT
    £11.96 ex VAT
    Save 53% Save %
  • Original price £2.11 - Original price £2.11
    Original price
    £2.11 inc VAT
    £2.11 - £2.11
    Current price £2.11 inc VAT
    £1.76 ex VAT

    Eaton EAD40B MCB 1 Pole 40A Type B 6kA 17.5 x 80 x 75mm Grey

    Eaton
    In stock

    Miniature circuit breaker (MCB) • DIN rail mountable and suitable for use with both pin and comb type busbar systems • Toggle position for positive...

    View full details
    Original price £2.11 - Original price £2.11
    Original price
    £2.11 inc VAT
    £2.11 - £2.11
    Current price £2.11 inc VAT
    £1.76 ex VAT
  • Original price £2.31 - Original price £2.31
    Original price
    £2.31 inc VAT
    £2.31 - £2.31
    Current price £2.31 inc VAT
    £1.93 ex VAT

    Eaton EAD16B MCB 1 Pole 16A Type B 6kA 17.5 x 80 x 75mm Grey

    Eaton
    In stock

    Miniature circuit breaker (MCB) • Toggle position for positive contact indication • Selectivity class 3 • Calibration temperature 40°C • Suitable f...

    View full details
    Original price £2.31 - Original price £2.31
    Original price
    £2.31 inc VAT
    £2.31 - £2.31
    Current price £2.31 inc VAT
    £1.93 ex VAT
  • Original price £2.11 - Original price £2.11
    Original price
    £2.11 inc VAT
    £2.11 - £2.11
    Current price £2.11 inc VAT
    £1.76 ex VAT

    Eaton EAD50B MCB 1-Pole 50A Type B 6kA - 17.5 x 80 x 75mm Grey

    Eaton
    In stock

    Miniature circuit breaker (MCB) • DIN rail mountable • Toggle position for positive contact indication • Selectivity Class 3 • Calibration temperat...

    View full details
    Original price £2.11 - Original price £2.11
    Original price
    £2.11 inc VAT
    £2.11 - £2.11
    Current price £2.11 inc VAT
    £1.76 ex VAT
  • Original price £27.85
    Original price £27.85 - Original price £27.85
    Original price £27.85
    Current price £13.91 inc VAT
    £13.91 - £13.91
    Current price £13.91 inc VAT
    £11.59 ex VAT

    Hager NBN320N MCB 3 Pole 10kA/15kA Type B 20A 3M

    Hager
    Low stock

    The NBN320N is a 20A, 10kA, triple pole, type B miniature circuit breaker (MCB) from Hager. It is part of the NBN range of MCBs, which are designed...

    View full details
    Original price £27.85
    Original price £27.85 - Original price £27.85
    Original price £27.85
    Current price £13.91 inc VAT
    £13.91 - £13.91
    Current price £13.91 inc VAT
    £11.59 ex VAT
    Save 50% Save %
  • Original price £1.85 - Original price £1.85
    Original price
    £1.85 inc VAT
    £1.85 - £1.85
    Current price £1.85 inc VAT
    £1.54 ex VAT

    Hager MT163 MCB SP 63A Type B

    Hager
    In stock

    Original price £1.85 - Original price £1.85
    Original price
    £1.85 inc VAT
    £1.85 - £1.85
    Current price £1.85 inc VAT
    £1.54 ex VAT
  • Original price £0.00 - Original price £0.00
    Original price £0.00
    £1.33 inc VAT
    £1.33 - £1.33
    Current price £1.33 inc VAT
    £1.11 ex VAT

    MK Electric H5903S MCB SP Type B 3A 6KA 230V 1 Module

    MK Electric
    In stock

    This is a Miniature Circuit Breaker, thermo -magnetic, current limiting type and are available with Type B operating characteristics. MCB operating...

    View full details
    Original price £0.00 - Original price £0.00
    Original price £0.00
    £1.33 inc VAT
    £1.33 - £1.33
    Current price £1.33 inc VAT
    £1.11 ex VAT
  • Original price £0.00 - Original price £0.00
    Original price £0.00
    £19.95 inc VAT
    £19.95 - £19.95
    Current price £19.95 inc VAT
    £16.63 ex VAT

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

    Siemens
    Low stock

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

    View full details
    Original price £0.00 - Original price £0.00
    Original price £0.00
    £19.95 inc VAT
    £19.95 - £19.95
    Current price £19.95 inc VAT
    £16.63 ex VAT
  • Original price £1.38 - Original price £1.38
    Original price
    £1.38 inc VAT
    £1.38 - £1.38
    Current price £1.38 inc VAT
    £1.15 ex VAT

    Volex VB10-B MCB Single Pole Type B 10A 6Ka

    Volex
    In stock

    Volex Accessories VB10-B MCB SP Type B 10A 6kA • Product: Circuit Breaker • Type: MCB • Pole Configuration: SP • Trip Type: Type B • Short Circuit ...

    View full details
    Original price £1.38 - Original price £1.38
    Original price
    £1.38 inc VAT
    £1.38 - £1.38
    Current price £1.38 inc VAT
    £1.15 ex VAT
  • Original price £0.00 - Original price £0.00
    Original price £0.00
    £26.42 inc VAT
    £26.42 - £26.42
    Current price £26.42 inc VAT
    £22.02 ex VAT

    ABB S203M-D50 MCB 3 Pole Type D 50A 2CDS273001R0501

    ABB
    In stock

    System Pro M Compact S200M Miniature Circuit Breakers Are Current Limiting. They Have Two Different Tripping Mechanisms, The Delayed Thermal Trippi...

    View full details
    Original price £0.00 - Original price £0.00
    Original price £0.00
    £26.42 inc VAT
    £26.42 - £26.42
    Current price £26.42 inc VAT
    £22.02 ex VAT
  • Original price £6.19
    Original price £6.19 - Original price £6.19
    Original price £6.19
    Current price £1.95 inc VAT
    £1.95 - £1.95
    Current price £1.95 inc VAT
    £1.63 ex VAT

    ABB S201M-D50 Miniature Circuit Breaker - 1P - Type D - 50A 10KA 2CDS271001R0501

    ABB
    In stock

    System Pro M Compact S200M Miniature Circuit Breakers Are Current Limiting. They Have Two Different Tripping Mechanisms, The Delayed Thermal Trippi...

    View full details
    Original price £6.19
    Original price £6.19 - Original price £6.19
    Original price £6.19
    Current price £1.95 inc VAT
    £1.95 - £1.95
    Current price £1.95 inc VAT
    £1.63 ex VAT
    Save 68% Save %

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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