From: john@ryepad.plus.com   
      
   Hello   
      
   In article <1237d$5567158c$43de0cc0$20554@news.flashnewsgroups.com>,   
      FLedbetter <0f8503901d844703eea1acecb7a4938a_1938@example.com> wrote:   
   > replying to BIGEYE, FLedbetter wrote:   
   > > tjke.gilmour wrote:   
   > >   
   > > We have had a catastrophic failure of an SF6 circuit breaker. This breaker   
   > > was used as a synchronising breaker for a CHP on our 11kV system.   
   > > Does anyone have or can point me to articles on failures (causes &   
   > effects)   
   > > of SF6 circuit breakers.   
   > > TIA   
      
      
      
   > I see several of these a  month across the US.I have many images and case   
   > study's I can share.   
   > The normal failure is not loss of gas but high contact resistance due to   
   > contaminates that are generated in the chamber that will increase the   
   > contact resistance thus creating heat that will damage springs and   
   > contacts.   
      
   > These poles can be reconditioned and this event can be avoided.   
   > Typically these are only a few types and the same issue is seen over and   
   > over again.   
   > Let me know if you want to communicate further.   
      
   > FL   
      
   You do not say where you are. The reference to 11 kV suggests an area of UK   
   interest. Several technologies have been used with SF6 in the UK including   
   puffer and rotating arc. Which type of circuit breaker was it that failed,   
   and did it fail during an operation, or when it was just sat on the system ?   
      
   John   
      
   --   
   John Rye   
   Hadleigh IPSWICH England   
   Web Site    
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