Current interruption in vacuum 
The vacuum circuit-breaker does not require an interrupting 
and insulating medium. In fact, the interrupters do not contain 
ionisable material. 
In any case, on separation of the contacts an electric arc 
is generated made up exclusively of melted and vaporised 
contact material.
The electric arc remains supported by the external energy 
until the current is cancelled in the vicinity of natural zero. At 
that instant, the rapid reduction in the load density carried 
and the rapid condensation of the metallic vapour, leads to 
extremely rapid recovery of the dielectric characteristics.
The vacuum interrupter therefore recovers the insulating 
capacity and the capacity to withstand the transient recovery 
voltage, definitively extinguishing the arc. 
Since high dielectric strength can be reached in the vacuum

• Vacuum interruption technique
• Vacuum contacts protected against oxidation and 
contamination
• Vacuum interrupter embedded in the pole
• Interrupter protected against shocks, dust and humidity
• Operation under different climatic conditions
• Limited switching energy
• Stored energy operating mechanism with anti-pumping
device supplied as standard
• Simple customisation with a complete range of 
accessories
• Fixed and withdrawable version
• Compact dimensions
• Sealed-for-life poles
• Sturdiness and reliability
• Limited maintenance
• Circuit-breaker racking in and racking out with door 
closed
• Incorrect and hazardous operations are prevented 
thanks to special locks in the operating mechanism and 
in the truck
• High environmental compatibility

SF6 GAS CIRCUIT BREAKER

• Autopuffer breaking technique
• Electric arc extinction without chopped current
• No restriking after breaking
• Rapid recovery of the dielectric properties of the means of extinction
• Withstand insulation voltage even at zero relative pressure (*)
• Breaking up to 30% of the rated breaking capacity even at zero 
relative pressure (*)
• Sealed-for-life poles
• Test for checking gas tightness carried out three times on each piece 
of apparatus
• Compact dimensions
• Fixed and withdrawable version
• Stored energy operating mechanism with anti-pumping device as 
standard common to the whole circuit-breaker series 
• Mechanical safety locks against incorrect operations
• Simple personalisation thanks to a complete range of accessories
• Maintenance-free
• SF6 gas pressure control device (on request).