Explain the working principle of Vacuum circuit breaker and
Air circuit breaker
Answer Posted / sk.raffique
When two current carrying contacts are separated in a
vacuum module, an arc is drawn between them. An intensely
hot spot or sparks are created at the instant of contact
separation from which metal vapor shoot off, constituting
plasma. The amount of vapour in the plasma is proportional
to the rate of vapour emission from the electrodes, hence
to the arc current. With alternating current arc, the
current decreases during a portion of wave and tends to
zero. Thereby the rate of vapour emission tends to zero and
the amount of plasma tends to zero. Soon after natural
current zero, the remaining metal vapour condenses and the
dielectric strength builds up rapidly, and restriking of
arc is prevented.
This principle is used in vacuum circuit breakers
| Is This Answer Correct ? | 45 Yes | 9 No |
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