8 December 2020

Advantage and disadvantages of SF6 circuit breaker

SF6 gas has high dielectric strength which is the most important quality of the material for use in electrical equipment ad in particular for the breaker it is one of the most desired properties. Moreover, it has a high rate of rising of dielectric strength after arc extinction. So here this article gives the advantages ad disadvantages of the SF6 circuit breaker to better understand this topic.

Advantages of SF6 circuit breaker:

  • SF6 gas has excellent insulating, as well as arc extinguishing, and also many other properties which are the greatest advantages of SF6 circuit breakers.
  • The gas has is inflammable and chemically stable. Their decomposition products are on explosive ad hence there is the risk of fire or explosion.
  • Electric clearance is very much reduced because of the high electric strength of SF6.
  • Its performance is not affected due to variations in atmospheric conditions.
  • These breakers give noiseless operations as well as there is an over-voltage problem because the arc is extinguished at natural current zero.
  • The closed gas enclosure keeps the interior dry. So that there is no moisture problem.
  • There is on reduction in electric strength because Caroon particles are formed during arcing.
  • It requires less maintenance and costly compressed air, systems are required.
  • SF6 performance various duties like clearing short line faults, switching, maintaining as well as opening unloaded transmission lines and transformer reactor, etc. without any problems.
  • Due to the superior is quenching property of SF6, such breakers have a very short arcing time.
  • There are no carbon deposits.
  • Low maintenance cost, light foundation requirement ad minimum auxiliary equipment.
  • SF6 breakers are totally enclosed and sealed from the atmosphere, they are particularly suitable where explosion.

Disadvantages of SF6 circuit breakers:

  • The entrance of moisture level in the SF6 breaker tank is very harmful to the breaker, and it causes several parts failures.
  • SF6 breakers are costly due to the reason for the high cost of SF6.
  • The internal parts need cleaning during periodic maintenance under a clean and dry environment.
  • A special facility requires transportation and the maintenance of the quality of gas.
  • SF6 gas is suffocating to some extent. In the case of leakage in the breakers takes the SF6 gas being heavier than the air and hence SF6 is settled in the surroundings and leads to the suffocation of the operating personnel.
  • SF6 gas has to be reconditioned after each and every operation of the breakers, some additional equipment is required for this purpose.