Arc Extinction In Circuit Breaker

This arc is dangerous on account of the energy generated in it in the form of heat which may result in explosive force.

Arc extinction in circuit breaker.

There are two methods of extinguishing the arc in circuit breakers. In high resistance method the arc resistance is made to increase gradually with the time so that the current force in between the two contacts is insufficient to maintain the arc. The arc resistance increases as the length of arc increases i e. It pushes away the moving contacts.

Principle of arc extinction. Principle of arc extinction in circuit breaker. 1 high resistance method. The main designing criteria of a circuit breaker is to provide appropriate technology of arc quenching in circuit breaker to fulfill quick and safe current interruption.

In doing so the contacts are pulled apart and the air blast moves away the. When opening air is required compressed air is admitted to the arc extinction chamber. Method of arc extinction. In air blast circuit breaker or in breaker where a gas flow is present between the electrical contacts the heat loss of arc plasma occurs due to convection process.

This is the main drawback of this method of arc extinction and so its use is restricted to dc circuit breakers and air break type ac circuit breakers of relatively low capacities of the. Therefore while designing the circuit breaker provision of mechanical strength to withstand such sudden release of large quantities of energy must be made. Principles and methods of arc extinction are discussed here. In this method the arc resistance is increases gradually so that current is reduced to such a value that heat is insufficient to maintain the arc.

In circuit breaker with plain break arc in oil arc in chutes or narrow slots nearly all the heat loss due to conduction. Arc extinction when the current carrying contacts of the circuit breaker are moved apart an arc is formed which insist for a short period after the separation of contacts. Cross section of the arc. There are two methods of extinguishing the arc in circuit breaker.

These are high resistance methods and low resistance or zero resistance method. As the separation between the contacts of breaker increases the arcing resistance also increases. Methods of arc extinction in circuit breaker. Heat loss from an arc in circuit breaker is takes place through conduction convection as well as radiation.