What is the difference between Restriking voltage and recovery voltage?

At which Voltage level restrike of ARC occurs is called as restriking Voltage. The normal frequency (60 Hz) r.m.s. voltage that appears across the contacts of the circuit breaker after final arc extinction in the steady state is the recovery voltage and is equal to the system voltage.

What is recovery voltage in circuit breakers?

Recovery Voltage is the normal frequency RMS voltage that appears across the contacts of the Circuit Breaker after final arc extinction. It is equal to the system voltage.

What is meant by Restriking voltage?

The voltage formed across two electrodes in an a.c. circuit at zero current and during the subsequent extinction of an arc between them, causing (if sufficiently high) the restriking of the arc; specifically that across the contacts of a circuit breaker, switch, etc., after they are separated.

Why do we use Restriking voltage?

The voltage appears across the breaker contacts at the moment of final current has a serious influence on the arc extinction process. Under the influence of this voltage, the arc tries to restrike and hence it is named as the restriking voltage.

What is restrike in a circuit breaker?

A breaker restrike is an abnormal arcing phenomenon, leading to a possible breaker failure. Eventually, this failure leads to interruption of the transmission and distribution of the electricity supply system until the breaker is replaced.

Why the value of RRRV is important for circuit breaker?

The amplitude factor is defined as the ratio of the peak of transient voltage to the peak system frequency voltage. (ii) Rate of Rise of Re-Striking Voltage (RRRV): In the latter case the voltage across the circuit breaker contacts rises slowly thereby giving longer time for building up of the dielectric strength.

On what factor does the rate of rise of restriking voltage depends on?

The rate of rise of re-striking voltage is directly proportional to the natural frequency. So, the rate of rise of re-striking voltage (RRRV) is dependent upon both the inductance and capacitance of the system.

Why recovery voltage is less than normal system voltage?

(d) Effect of Armature Reaction: The recovery voltage is less than the normal system voltage because of demagnetizing effect of armature reaction. The short-circuit currents are of lagging power factor and are flowing in the generator windings. They have a demagnetizing armature reaction.

What is rate of rise of restriking voltage?

Rate of Rise of Restriking Voltage (RRRV): The RRRV is defined as the slope of the steepest tangent to the restriking voltage curve. It is expressed in volts per microsecond.

How is the Restriking voltage measured?

The transient voltage that appears across the circuit breaker contacts at the instant of arc extinction is called restriking voltage. It is measured in peak value.