Circuit Constants in Circuit Breaking

Current Chopping

Current Chopping: When interrupting small inductive currents such as transformer excitation currents, circuit breakers tend to clear before the natural current zero is reached. This is because the low-current ionized conducting path may become prematurely unstable, forcing the low arc current to zero along a very steep wave front. This phenomenon is known as current …

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Characteristics of Rate of Rise of Restriking Voltage

Characteristics of Rate of Rise of Restriking Voltage: The important Characteristics of Rate of Rise of Restriking Voltage which affect the circuit breaker performance are: amplitude factor, rate of rise of restriking voltage (RRRV). Amplitude Factor: The amplitude factor is defined as the ratio of the peak of transient voltage to the peak system frequency …

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Recovery Voltage

Recovery Voltage: Recovery Voltage – While closing or opening the circuit breaker, the circuit constants play an important role. It was noticed in practice a circuit breaker that would operate satisfactorily at one point on a system may not do so at another, showing that the circuit conditions have some influence on the circuit breaker …

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Circuit Breaker Rating

Circuit Breaker Rating: The ratings of a circuit breaker refer to the characteristic values that define the working conditions for which the circuit breaker is designed and built. Circuit breakers must be capable of carrying continuously the full load current, without excessive temperature rise, and should be capable of withstanding the electrodynamic forces. The circuit …

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