SF6 Sulphur Hexafluoride Circuit Breaker 35KV RMU Switchgear VCB

Product Introduction

The sulfur hexafluoride circuit breaker is a circuit breaker that uses sulfur hexafluoride (SF6) gas as the arc extinguishing medium and insulating medium. Referred to as SF6 circuit breaker. The use of sulfur hexafluoride as an arc extinguishing medium in circuit breakers began in the early 1950s. Due to the excellent characteristics of this gas, the voltage and current parameters of the single-break of this circuit breaker are much higher than those of compressed air circuit breakers and oil-less circuit breakers, and it does not require high air pressure and a considerable number of serial breaks. In the 1960s and 1970s, SF6 circuit breakers have been widely used in ultra-high voltage and large-capacity power systems. In the early 1980s, SF6 circuit breakers with 363 kV single-break, 550 kV double-break and rated breaking currents of 80 and 100 kA were successfully developed.

Chemical properties

The chemical effect of SF6 gas itself is very stable, and has a very high insulation strength. Under atmospheric pressure and at a temperature of at least 500°C, SF6 has high chemical stability. In the normal temperature range, it has no reaction with metals commonly used in electrical equipment. The dangerous temperature of SF6 decomposition is about 600℃. At this time, SF6 decomposes to form low-fluorine compounds of sulfur. Therefore, SF6 is quite stable at least within the A-class insulation temperature of electrical equipment, that is, 105℃.