Answer / guna

VCB - Vacuum circuit breaker, which is used at HT side of
transformer(High voltage & low current side). the arc
quenching medium is vacuum.

SF6 - sulfur hexafluoride circuit breaker, which is used at
both HT & LT side of transformer..the arc quenching medium is
SF.

Answer / avinash pralhad nikam

The arc quenching capacity of SF6 is more than the vaccum. also sf6 has more IR value than that of vaccume . also sf6 is more electronegative than vaccum.

Answer / vidya sagar reddy

In VCB the arc quenching media is Vaccume. We can use up to 33KV. SF 6 arc quenching media is Sulfur hexa fluoride gas. Which is very effective comparing with VCB. Available only above 33KV.

Answer / jitender

sf6 breaker has low maintenance other than the vcb
it's life is more than vcb.

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