Difference between re-ignition and re-strike in switching devices

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  • Re-ignition is re-establish of arc after arc extinction within one fourth of cycle from final current zero. It may occur because of small distance between two contacts. Due to that, contact gap breakdown and arc re-ignite. The re-ignition is not harmful as it does not give any overvoltage. At next current zero instance only, arc gets quench as the distance between two contact becomes sufficient to withstand Transient Recovery Voltage(TRV).
Fig. Current waveform with re-ignition and re-strike

  • Re-strike is re-establish of arc after one fourth of cycle from final current zero. It occurs due to capacitive current switching. In capacitive current switching, a single restike gives 4 times voltage rise. It leads to overvoltage which can damage dielectric medium.
  • Re-striking is more severe than re-ignition.


Comments

  1. mattSeptember 9, 2024 at 5:50 PM

    Hi, WeEngineers, thank you for your excellent explain for "Difference between re-ignition and re-strike in switching devices". I am a little bit confused, may I know the "cycle" in Fig. means it included full positive half wave and negative half wave ? However 1/4 cycle in the Fig. looks like just only in negative half wave. If the Fig. is correct, , the 1/4 cycle will be 20/2/4 = 2.5 ms in 50 Hz power system. To my understanding, 1/4 cycle will be 50/4 = 5 ms. As above, may I know what is your suggestion? Thank you very much and have a nice day.

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