Vacuum Circuit Breaker
A vacuum circuit breaker is such kind of circuit breaker where the arc quenching takes place in vacuum. The technology is suitable for mainly medium voltage application. For higher voltage vacuum technology has been developed but not commercially viable. The operation of opening and closing of current carrying contacts and associated arc interruption take place in a vacuum chamber in the breaker which is called vacuum interrupter.
Advantages of Vacuum Circuit Breaker (VCB)
Service life of vacuum circuit breaker is much longer than other types of circuit breakers. There is no chance of fire hazard as oil circuit breaker. It is much environment friendly than SF6 Circuit breaker. Beside of that contraction of VCB is much user friendly. Replacement of vacuum interrupter (VI) is much convenient.
Types & Ranges of VCB
GES is the largest manufacturer of three types i.e., INDOOR, OUTDOOR & O/D KIOSK and also We provide different ranges of VCBs i.e., from 3.3KV to 33KV based on customers’ requirement.
Minimum Oil Circuit Breaker or MOCB
These types of circuit breakers utilize oil as the interrupting media. However, unlike bulk oil circuit breaker, a minimum oil circuit breaker places the interrupting unit in insulating chamber at live potential. The insulating oil is available only in interrupting chamber. The features of designing MOCB is to reduce requirement of oil, and hence these breaker are called minimum oil circuit breaker.
Bulk Oil Circuit Breaker or BOCB
Bulk oil circuit breaker or BOCB is such types of circuit breakers where oil is used as arc quenching media as well as insulating media between current carrying contacts and earthed parts of the breaker. The oil used here is same as transformer insulating oil.
SF6 Circuit breakers
SF6 Circuit breakers are made from 72-550kV with interruption current of 20 to 63 kA and rated current of 1,200 to 12000 amps.
Because of the properties of SF6 gas such as excellent arc quenching, high electronegative nature, and excellent dielectric strength SF6 circuit breakers are popular for high voltage applications and above.
SF6 Circuit Breakers Advantages:
- Excellent insulating, arc extinguishing, physical and chemical properties of SF6 gas is greater advantage of SF6 circuit breakers
- The gas is non-inflammable and chemically stable. The decomposition products are non-explosive i.e, rhere is no risk of fire or explosion
- Electrical clearances are very much reduced because of high dielectric strength of SF6
- Its performance is not affected due to variation in atmospheric conditions
- It gives noiseless operation it does not make sound like air-blast circuit breaker during operation
- Therefore is no reduction in dielectric strength of SF6 since no carbon particle is formed during the arcing
SF6 Circuit Breakers Applications:
SF6 Circuit breakers are mostly employed for High voltage applications. Because of the above said features and properties of SF6 gas they are mostly employed in switching duties related to high voltage and extra high voltage applications.