Define: i) Arc voltage, ii) Recovery voltage, iii) Restriking voltage, iv) RRRV

Define: i) Arc voltage, ii) Recovery voltage, iii) Restriking voltage, iv) RRRV
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Answer :

i) Arc Voltage: The voltage existing between the circuit breaker contacts during arcing is called as the arc voltage. It is low value compared to the system rated voltage. Normally it is around 3% to 5% of the rated system voltage. 


ii) Recovery voltage: The normal power frequency voltage that appears across the contacts after the arc is finally extinguished and the transients have fully disappeared is the recovery voltage. 


iii) Restriking voltage: The transient voltage that appears across the contacts of the circuit breaker at the instant of the arc getting extinguished is called as the restriking voltage. 


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

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