Which of the following circuit breakers has high reliability & minimum maintenance?

Which of the following circuit breakers has high reliability & minimum maintenance? 

(A) Bulk oil type CB (B) Air blast CB (C) Vacuum CB (D) Sulphur hexafluoride CB 
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1 Answer

Answer :

Which of the following circuit breakers has high reliability & minimum maintenance? 

(A) Bulk oil type CB (B) Air blast CB (C) Vacuum CB (D) Sulphur hexafluoride CB 

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SF6 has highest dielectric capacity.but maintainence is too costly since SF6 converts to SF4 andSF2 and it is highly poisness.

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