Arc phenomena
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Transcript of Arc phenomena
Md. Merajul IslamID:5551310212nd batch, 5th
semesterDept. of EEE
Presented ToFarha Nazrun
Course teacherPower System-I
Arc phenomena
Resulting a current through normally nonconductive media such as air.
Temperature ionize the medium contacts(Air or oil)
Factors responsible for maintaining Arc…
1. P.D. between the contacts2. Ionized particles between contacts
Arc resistance depends on the following factor…..
1. Degree of ionization 2. Length of arc
There are two method to extinction of arc…
1. High Resistance method.2. Low resistance method or zero current method.
Methods of increasing arc resistance……..
1. Lengthening of arc.2. Cooling of arc.3. Reducing cross section area of arc.4. Splitting the arc.
Low Resistance or Current Zero Method...
High power a.c. circuit breakers employ this method for arc extinction.
There are some circuit breaker use different arc extinction system…
Ari-blast circuit breaker
Oil circuit breaker
SF6 circuit breaker
Vacuum circuit breaker
Disadvantages……
arc flashes produce concentrated radiant energy that can cause severe burns to
unprotected workers Numerous physical
hazards Dangerous and costly
industrial accident.
Conclusion……Arc flash accidents are very dangerous. These energy levels can produce severe burns leading to death for those within close to the arc flash.
Thanks