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April 29, 2020   photos  

Vacuum, SF6 and oil circuit breaker. Modern systems are phasing out oil circuit breakers because of their susceptibility to fire. VCB suitable for 11kv. Oil CB for 33kv, GCB (sf6) used for 132kv and more.Vacuum Circuit Breaker (VCB). I Sf6 circuit breaker and then air blast circuit breaker. Generally for 33 kV used of OCB, GCB (SF6) this two types only. Vacuum circuit breaker is suitable for 11kv. Finally, Oil circuit breaker & vacuum circuit breakers.