Arc Extinction In Circuit Breaker

It pushes away the moving contacts.

Arc extinction in circuit breaker.

Therefore while designing the circuit breaker provision of mechanical strength to withstand such sudden release of large quantities of energy must be made. 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 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. Principle of arc extinction in circuit breaker.

Principles and methods of arc extinction are discussed here. There are two methods of extinguishing the arc in circuit breakers. 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. There are two methods of extinguishing the arc in circuit breaker.

Heat loss from an arc in circuit breaker is takes place through conduction convection as well as radiation. The arcing resistance increases with decrease in the cross sectional area of the arc. The arc resistance increases as the length of arc increases i e. In circuit breaker with plain break arc in oil arc in chutes or narrow slots nearly all the heat loss due to conduction.

As the separation between the contacts of breaker increases the arcing resistance also increases. When opening air is required compressed air is admitted to the arc extinction chamber. 1 high resistance method. 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.

The air blast needs an additional compressed air system which supplies air to the air receiver. These are high resistance methods and low resistance or zero resistance method. This arc is dangerous on account of the energy generated in it in the form of heat which may result in explosive force. Cross section of the arc.

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. Principle of arc extinction. In doing so the contacts are pulled apart and the air blast moves away the. Method of arc extinction.