When the circuit breaker receives a tripping signal, the operating mechanism acts, causing the moving contact to move from the closed position to the open position. At the moment when the moving and fixed contacts separate, an arc is generated due to the increase in the contact resistance between the contacts.
The vacuum environment in the vacuum interrupter enables the arc to be quickly extinguished when the current crosses zero, thus achieving the disconnection of the circuit.
During the closing process, the operating mechanism makes the moving contact move towards the fixed contact until they come into contact and complete the closing operation, thereby connecting the circuit.
