When the moving and static contacts of the vacuum circuit breaker are opened under the action of the operating mechanism, an arc is generated between the contacts, and the surface of the contacts volatilizes steam at high temperatures. Due to the special shape of the contacts, a Magnetic field, the arc moves quickly along the tangent direction of the contact surface under the action of this magnetic field, and part of the metal vapor is condensed on the metal cylinder (shielding cover). The arc is extinguished when it naturally crosses zero, and the medium strength between the contacts is rapid again. Recovered.
1. Closing process: When the closing coil of the operating mechanism is energized, the closing iron core is sucked in, and the movable conductive rod of the vacuum interrupter is moved through the arm and the connecting rod to close the circuit breaker.
2. Opening process: When the opening coil of the operating mechanism is energized, the opening iron core is attracted to release the lock, and the circuit breaks quickly under the action of the opening spring.
3. Arc extinguishing process: The moving and static contacts of the vacuum circuit breaker are provided with spiral grooves, so that a transverse magnetic field is applied to the axial direction of the arc. When the arc is driven (longitudinal magnetic field for large-capacity vacuum circuit breakers), the arc is high Rotate to avoid overheating of the face contacts.