Circuit breakers Sulphur hexafluoride

With the availability of 3.3 and 6.6 kV vacuum contactors the control of HT motors up to 6.6 kV systems has now become easier and economical, compact and even more reliable. For 11 kV. systems, vacuum as well as SF (Sulphur hexafluoride) breakers can be used. The HT motor s switching and protection through a vacuum contactor provides a replica of an LT system. The earlier practice of using an HT OCB, MOCB, or an air blast circuit breaker for the interruption of an HT circuit is now a concept of the past. 

EINECS 219854-2 Elegas Esaflon Hexafluorure de soufre HSDB 825 Sulfur fluoride, (OC-6-11)- Sulfur fluoride (SFe), pC-6-11)- Sulfur hexafluoride Sulphur hexafluoride UN1080. Used in electrical circuit breakers and in electronic ultra-high frequency piping. Gas mp = -51° soluble in oil. Montedison UK. 

Another precaution against the risks associated with the use of oil-filled switchgear is to replace it with switchgear that uses an alternative insulating medium. Options include sulphur hexafluoride (SFe) gas-filled enclosures, air insulation, and vacuum circuit breakers. The SFe variety is beginning to lose favour because of the environmental and toxic hazards that the gas poses, so vacuum and air-insulated gear is now preferred by most high... 

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