How do you calculate Restriking voltage?
How do you calculate Restriking voltage?
For a re-striking voltage having a single frequency transient component the RRRV is obtained by dividing the maximum amplitude of the oscillation by the duration of the first half wave. Higher values of natural frequencies can be related with higher rates of rise of re-striking voltage.
What is Restriking current?
It is the transient voltage that appears across the contacts at or near current zero during arcing period. It is the transient voltage that appears across the contacts at or near current zero during arcing period. …
What are 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.
What is prospective voltage?
“prospective” touch voltage [IEV 195-05-09; 826-11-03] • voltage between simultaneously accessible conductive parts. when those conductive parts are not being touched by a person or an animal.
What is the Restriking voltage Mcq?
Q1. What is restriking voltage? The transient voltage that appears across the circuit breaker contacts at the instant of arc extinction.
What is average RRRV in circuit breaker?
Voltage that appears between the contacts of the circuit breaker after arc extinction during opening process while clearing a fault. The Rate of Rise of Recovery Voltage (RRRV) is defined as peak transient recovery voltage divided by the total time from zero voltage to peak voltage.
What is meant by Restriking voltage and recovery voltage?
The expression for the restriking voltage is expressed as. The transient voltage vanishes rapidly due to the damping effect of system resistance, and the normal frequency system voltage is established. This voltage across the breakers contact is called recovery voltage.
What is rate of rise of restriking voltage?
BS 116 specify the standard for evaluating amplitude factor. 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.
What is Restriking voltage 1 point?
The transient voltage that appears across the contacts of the circuit breaker at the current zero period during arcing is known as Restriking voltage. The rate of rise of re-striking voltage is directly proportional to the natural frequency.
What is RRRV What is its unit?
It is the rate of increase of restriking voltage and is abbreviated by R.R.R.V. its unit is kV/m sec.
How do I reduce RRRV?
Apply surge capacitors at terminal of circuit breaker to reduce RRRV.
What is RRRV in circuit breaker?
Voltage that appears between the contacts of the circuit breaker after arc extinction during opening process while clearing a fault. • The Rate of Rise of Recovery Voltage (RRRV) is defined as peak transient recovery voltage divided by the total time from zero voltage to peak voltage.
What do you mean by restriking voltage?
The transient voltage that appears across the circuit breaker contacts immediately after the arc extinction or at current zero during the arcing period is called Restriking Voltage. This voltage is so named because the arc can restrike only during the existence period of this transient voltage.
How does a re-striking voltage transient work?
The re-striking voltage transient for such circuits can have several component frequencies ranging from a few Hz to several kHz. When the breaker contacts are opened and the arc finally extinguishes at some current zero, a voltage v is suddenly applied across capacitor and therefore, across the circuit breaker contacts.
What is the maximum value of re-striking voltage?
The above expression is the expression for re-striking voltage where V max is the peak value of recovery voltage (phase-to-neutral), t is time in seconds, L is inductance in henrys, C is the capacitance in farads and v is the re-striking voltage in volts. The maximum value of re-striking voltage is 2 V max and occurs at t = π /w or t = π √LC .
How do you find the rrrv of re-striking voltage?
For a re-striking voltage having a single frequency transient component the RRRV is obtained by dividing the maximum amplitude of the oscillation by the duration of the first half wave. Higher values of natural frequencies can be related with higher rates of rise of re-striking voltage.
