TJ-1.14/630 1.14KV 630A vacuum interrupters for AC Contactors
structure type
The ceramic outer casing vacuum interrupter is mainly composed of a gas-tight insulating shell, a conductive loop, a shielding system, a contact, a bellows and the like.
working principle
The vacuum interrupter in the vacuum bubble is an electric vacuum device that utilizes a high vacuum working insulation arc extinguishing medium to realize the on/off function of the power circuit by a pair of contacts sealed in a vacuum. When it breaks a certain value of current, at the moment of separation of the moving and static contact, the current shrinks to a point where the contact is just separated, and the resistance between the electrodes increases sharply and the temperature rapidly increases until the evaporation of the electrode metal occurs. Extremely high electric field strength results in extremely strong emission and gap breakdown, resulting in a vacuum arc. When the power frequency current approaches zero, it is also an increase in the contact opening distance. The plasma of the vacuum arc quickly spreads around. After the arc current crosses zero, the medium in the contact gap quickly changes from the conductor to the insulator, and the current is broken. Due to the special configuration of the contacts, the contact gap during the arcing will produce an appropriate longitudinal magnetic field. This magnetic field can evenly distribute the arc on the contact surface, maintaining a low arc voltage, thus making the vacuum interrupter have a higher arc. Post-media strength recovery rate, small arc energy and small corrosion rate. In this way, the ability and service life of the vacuum interrupter breaking current is increased.