when we are going to higher voltage level in substations why
we are using Sf6 circuit breakers instead of Vacuum circuit
breakers.

Answer Posted / raul

sf6 CB has far superior arc quenching properties as
compared to other CBs due to tremendous amount of capacity
of SF6 gas to absorb free electrones in the contact
space.........so the dielectric strength is very
high...........and also there is a cost consideration
factor which makes the use of VCB a less viable
proposition.............

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