Explain the working principle of Vacuum circuit breaker and
Air circuit breaker

Answer Posted / t eswara rao

During the breaker opening operation an arc will be produced
in between moving contacts and fixed contacts. It require
any medium to produce an arc. If there is no medium, there
is no arc. No medium means it is empty or VACUUM. So this
technique is used for quenching the arc in the vacuum
circuit breakers. So it is very clear that in perfect
vacuum, there is no arc produced.

In Air Circuit Breaker, air is used as arc quenching medium.
it is very simple in construction and cost is also low where
as the Vacuum circuit breaker is very costly due to its its
complicated construction for maintaining the vacuum in the
vacuum chamber

Is This Answer Correct ?    68 Yes 19 No



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