How to connect mcb in a house.

MCB circuit breaker for house wiring
Circuit breakers

Before I proceed to show you how to connect MCB in a house, allow me to define an MCB.

MCB stands for a miniature circuit breaker. As the name implies, an MCB is an electrical device or component that breaks the circuit. It can break a circuit either intentionally or forcefully due to a short circuit. Intentionally when you switch the circuit breaker isolate a bulb or any machine that is connected to that circuit.

A circuit breaker is designed to interrupt power to a complete circuit when there is an overload in that circuit. What do you need for you to connect a circuit breaker successfully? You will need a distribution board where all the cables and wires start before thy distribute electricity throughout the house.

Where is MCB connected to which wire?

I have said that you need a distribution board or electrical panel for you to connect an MCB. How many wires are on the distribution board? There are basically 3 wires in the electrical panel these wires live or hot wire, neutral and earth wires.

The live wire is the one that carries electricity to various electrical appliances in the home. While the neutral wire takes the electricity from the electric appliances back to the distribution board. The earth wire is a protective conductor it prevents electrical shocks and many other electrical hazards from happening.

Which wire is connected to the MCB? The live wire is connected to the MCB.

How do you attach an MCB?

There are two ways you can use to attach an MCB. These methods or ways of attaching the MCB is determined by the construction of the circuit breaker you want to mount. They are circuit breakers that are easily mounted using a din rail and other circuit breakers are mounted using an MCB tray.

Which MCB is used for a house?

They are basically three main types of MCBs.These are B, C and D.The type of MCB is mainly determined by the level of a magnetic strip of the circuit breaker. Circuit breakers will protect equipment and people mainly by using, Overload protection and magnetic fault protection.

Overload protection: This feature of a circuit breaker, prevents accidental overloading in a load fault situation.

Magnetic fault protection: this characteristic of MCBs operates when the fault reaches a predetermined level and trips the MCB within one-tenth of a second.

Short circuit rating: Short circuit rating is intended to protect against heavy faults in thousands of amperes. The ability of a circuit breaker to operate under these conditions gives its short circuit rating. In kilo amperes(KA). For domestic applications, 6KA is adequate whereas, for commercial and industrial applications,10KA and above short circuit rating is required.

MCB TypeTripping timeOperating time
B3 to 5 times full load current0.04 to 13 seconds
C5 to 10 times full load current0.04 to 5 seconds
D10 to 20 times full load current0.04 to 3 seconds

Type B is Mainly suitable for domestic applications and resistive loads.

What is a 32A MCB used for?

A 32A MCB is mainly used in socket outlet circuits and cooker circuits. The number of 32A circuit breakers on the distribution board is determined by the number of socket outlets and the number of cookers in the house.

How much ampere in an MCB is best for a home?

Well in a home there are various electrical loads. Each load or appliance draws a certain amount of current from the electric supply. In general terms, 100A is sufficient for a home.

Mind you there will never be a time when all electrical appliances in a home will operate at the same time. When this happens, it is in very rare circumstances. On the lower end, 60A is sufficient for a home setting. What ampere in an MCB is best for a home?60A-100A is suitable for a single-phase home installation.

What size MCB for 2.5mm cable?

When using a 2.5mm squared cable, you can use either a 20A or 32A circuit breaker. This is dependent on the load or appliances that you are going to connect.

For example, when you use it to supply electric power to that air conditioner, you will use a 20A circuit breaker. And if you have a 2.5mm squared cable to supply socket outlets, you will use a 32A circuit breaker.

What is a 20A MCBB used for?

A 20A circuit breaker is used in airconditioner circuits and water heater circuits for a 230V electrical power supply.

What is a 10A mcb used for?

10A circuit breakers are mostly used for lighting circuits in homes and control circuits single phase electrical pumps.

What is the maximum load for a 2.5mm cable?

The maximum load that a 2.5mm cable can carry safely, is 4000W or 4kw.

What are your thoughts on MCBs ?what questions or ideas do you have? Write them in the comments section below.

Author: Themba Mbewe

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