1 high resistance method.
Arc extinction in circuit breaker.
Hence the current is.
Methods of arc extinction in circuit breaker.
Principles and methods of arc extinction are discussed here.
When opening air is required compressed air is admitted to the arc extinction chamber.
The arc resistance increases as the length of arc increases i e.
As the separation between the contacts of breaker increases the arcing resistance also increases.
In doing so the contacts are pulled apart and the air blast moves away the.
Principle of arc extinction.
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.
There are two methods of extinguishing the arc in circuit breakers.
These are high resistance methods and low resistance or zero resistance method.
Principle of arc extinction in circuit breaker.
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.
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.
The arcing resistance increases with decrease in the cross sectional area of the arc.
There are two methods of extinguishing the arc in circuit breaker.
It pushes away the moving contacts.
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.
Method of arc extinction.
Heat loss from an arc in circuit breaker is takes place through conduction convection as well as radiation.
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.
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.
The air blast needs an additional compressed air system which supplies air to the air receiver.