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1. Fundamental of arc interruption

2. Ionization of gases
 Thermal Ionization
 At normal temperature
 At 3000 degree C
 At 6000 degree C
 Ionization by Collision
 Thermal Emission from Surface of Contacts
 Secondary Emission at Contacts Surface
Field Emission at Contact Surface
Photoemission

4. Deionization
 Recombination
 Diffusion
 Conduction of Heat

5. Electric Arc

6. Arc formation in AC Circuit Breakers

7. High Resistance Interruption
• Lengthening the arc by means of arc runners

8. • Splitting of arc

10. Arc Interruption Theories
• Slepian’s Theory