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Select the material having the highest arc interrupting capability when used as a medium in circuit breaker.

Select the material having the highest arc interrupting capability when used as a medium in circuit breaker. Correct Answer High vacuum

Vacuum circuit breaker has a high insulating medium for arc extinction as compared to the other circuit breaker. The vacuum circuit breaker has mainly two phenomenal properties.

  • High insulating strength: In comparison to various other insulating media used in circuit breaker vacuum is a superior dielectric medium. It is better than all other media except air and SF6, which are employed at high pressure.
  • When an arc is opened by moving apart the contacts in a vacuum, an interruption occurs at the first current zero. With the arc interruption, their dielectric strength increases up to a rate of thousands time as compared to other breakers.

 

The above two properties make the breakers more efficient, less bulky, and cheaper in cost. Their service life is also much greater than any other circuit breaker, and almost no maintenance is required.

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