Silicon Rubber / Solid Epoxy Resin Bushing ZW20 Outdoor aeg Air Circuit Breakers l&t
Air Circuit Breakers echnical Parameter

 
Summary
As a kind of maintenance-free outdoor vacuum switch, it has the features of three-phase non-segregated longitudinal magnetic field vacuum quenching of arc, SF6 as the insulation and the insulation of silicone rubber/solid epoxy resin.
ZW20 series circuit breaker use three-phase non-segregated structure and has the features of stable and reliable breaking performance, no combustion and explosion danger, maintenance-free, light weight (two-thirds of similar products ), high cycle life (mechanical operating life is 10000 times) and so on. New designed spring operating mechanism is exposed in SF6 to effectively avoid traditional spring operation mechanism’s design defects, such as stagnation and rustiness, making a significant improvement in reliability.
 
Air Circuit Breakers Scope of Application
ZW20 series circuit breaker is mainly used to break and close load current, overload current and short-circuit current in the electric power system. It is used to protect and control the power distribution system in transformer substation, industrial and mining enterprises, and it is especially suitable for the transformation of the power network in rural and city. This circuit breaker can be used with FTU/dividing switch controller, so as to automatically detect, isolate and alarm the faults in main line’s section and branch, and monitor line operation. And it has the function of automatically recovering power supply in the fault segment. After adding measure and protection, control and communication functional module to the switch, it can satisfy the requirement of power distributing automation.
 
Air Circuit Breakers The Main Features Of This Product
1. Vacuum arc technology
  The vacuum tube that ZW20 series circuit breaker uses is made by the technology of three-phase non-segregated longitudinal magnetic field vacuum quenching of arc, which is one of the most advanced open circuit device. Long-term field operation experience proves that the vacuum tube which uses this technology has the features of long life and high reliability. With this technology the spiral groove structure on the active and static contactor makes the current that goes through the contact produces longitudinal rotating magnetic field, which can accelerate the diffusion of ionizing particle and reduce arc energy. And then the shielding case of special alloys will rapidly absorb energy of diffused arc. This process makes the vacuum tube own the advantages of small heat value, short arc time, long life etc.
2. Silicon rubber/solid epoxy resin bushing
  ZW20 series circuit breaker adopts imported outdoor special materials, silicon rubber and epoxy resin, and adopts advanced APG vacuum casting technology and the newest various testing means in order to ensure the quality of the products. Experiment and 20 years’ outdoor operation experience shows that silicon rubber and epoxy resin solid insulation materials have no surface carbonization and corrosion in corona and controllable arc discharge cases, which makes the performance of the circuit breaker has great improve under the condition of ultraviolet ray, humidity, high salinity and other corrosion factors.
3. The technology of SF6 insulation
   ZW20 series circuit breaker uses SF6 on ompa as insulating medium. The good insulation of SF6 can effectively prevent the product have the accidents because of internal condensation. And meanwhile, the design in the circuit breaker can make SF6 in in the air insulation to meet the needs of the industrial frequency compression, alternate with 42kv, fracture 48kv level, and ensure the safety operation of the product.
 
4. Explosion and pressure relieving device
    The top-cover of the case of ZW20 series circuit breaker is designed as high-pressure relieving channel. When the pressure of SF6 sharply increases because of some abnormal reason in the case, the top-cover will rapidly bound up to relieve high pressure, which can avoid endangering of operators and public safety.
5. Spring operation mechanism
   ZW20 series circuit breaker uses simple and reliable spring operation mechanism, which making the circuit breaker has small size and light weight. This mechanism use imported spring wire to keep enough spring force under the long-time running state; the rotational part uses bearing structure and surface treatment method with Zinc, Nickel and Cobalt alloy to ensure that the product can stay in a long-time stable and reliable operating state in harsh environment.