Air Circuit Breakers: Their Types and Uses

Whenever there is some fault in the electrical system or the current jumps above the

safe level, the circuit breakers automatically trip themselves to avoid any complications.

If you don’t have a circuit breaker installed in your house, then there are a lot of

chances of having simple wiring problems or equipment damage. The circuit breakers

help to protect for overload, short circuit and earth fault/ground fault. Circuit breakers

are of various types one of which is the air circuit breaker. As the name suggests, air

circuit breakers make use of compressed air to blow out the arc.

Air circuit breakers are used for a common protection of plants, user complexes, electric

machines like generators, motors, transformers, capacitors, etc. An air circuit breaker is

used in low as well as high voltage current. They are frequently used in electricity

sharing systems and NGD for voltage equal to 15 KV like in houses to supply electricity

to various electrical equipments. Air circuit breakers comprise of an operating device

that is uncovered and exposed to the atmosphere. The majority of air circuit breakers

are used in indoor substations.

When the breaker trips and opens, the current that has been flowing in the house is

broken. This generates an electrical arc which is cooled and extinguished in a controlled

way. When the tripped circuit is contacted again, the interrupted power is brought back.

When there is a use of compressed air to put out the electrical arc, then this type of

circuit breaker is called as an air circuit breaker.

An air circuit breaker consists of three main types of contacts:

1. The main contacts: The main contacts are responsible for carrying the load

current under usual circumstances. They are made of good conducting materials

like copper, silver or copper with silver plating. Because the main contacts cannot

prevent the harm caused by arching, it is not responsible for making or breaking

current.

2. Arching contacts: These contacts are used to make or break the current.

3. Arching Horns: When a current is made on the arching contacts, it is sent to the

arching horns during the arching contacts opening.

Air circuit breakers are comparatively reasonable and can be installed uncomplicatedly.

This is the reason that they are used the maximum amongst all types of circuit breakers.