11kv 33 Kv Vcb Insulated 3 Phase Drawout 10000 Mechanical Long Life

Vacuum Arc Recovery Phenomenon:
High vacuum possesses extremely high dialectic strength. At current zero the cathode spot extinguishes within 10–8 second and after this the original dielectric strength is established very soon. This quick return of high dielectric strength is, of course, due to the fact that the vaporized metal which is localized between the contacts, diffuses rapidly due to absence of gas molecules. The metal molecules are blown at high speeds to the glass walls and condense there. After arc interruption the recovery strength during the first few microseconds is 1 kV/µs for an arc current of 100 A, as compared with 50 V/µs in case of air gap.
Because of the attributes of vacuum interrupters, vacuum circuit breakers can be employed without reservations for fault clearing in any location on a system. They are capable of handling the severe recovery transients associated with short line faults or faults close to a transformer without any difficulty. All forms of load switching can be performed with the same ease.

XK 11kv/33kv insulated high voltage 3 phase drawout vacuum circuit breaker vcb