What is a vacuum circuit breaker?
What is a vacuum circuit breaker?
A circuit breaker that uses vacuum as the arc extinguishing medium is called a vacuum circuit breaker. In this type of circuit breaker, the fixed and movable contacts are enclosed in a permanently sealed vacuum circuit breaker. The arc is extinguished as the contacts are separated in high vacuum. Mainly used for medium voltage from 11KV to 33KV.
Compared with other circuit breakers, vacuum circuit breakers have higher arc extinguishing insulating medium. The pressure inside the vacuum interrupter is about 10-4 Torrent, and at this pressure there are very few molecules in the interrupter.
Vacuum circuit breakers have two main characteristics.
1. High Dielectric Strength: Vacuum is a superior dielectric medium compared to various other insulating mediums used in circuit breakers. It outperforms all other media except air and SF6, which are used at high pressure.
2. When the arc is opened by removing the contacts in a vacuum, the interruption occurs at the first zero current. As the arc breaks, their dielectric strength increases thousands of times compared to other circuit breakers.
The above two characteristics make the circuit breaker more efficient, smaller and less expensive. They also last much longer than any other circuit breaker and require little maintenance.
The structure of vacuum circuit breaker
Its structure is very simple compared to any other circuit breaker. Its structure is mainly divided into three parts, namely the fixed contact, the moving contact and the arc extinguishing cover placed in the arc extinguishing chamber.
The housing of the vacuum circuit breaker is made of glass, as the glass housing facilitates the external inspection of the circuit breaker after operation. If the glass turns milky white from its initial silver mirror, it's a sign that the circuit breaker is losing its vacuum.
The fixed and moving contacts of the circuit breaker are placed in the arc shield. The pressure in the vacuum interrupter was maintained at about 10-6 Torr while sealing. Depending on the operating voltage, the moving contacts of the circuit breaker can move a distance of 5 to 10 mm.
Metal bellows made of stainless steel are used to move the moving contacts. The design of the metal bellows is very important because the life of the vacuum circuit breaker depends on the repeated operation of the components satisfactorily.
JGGY’S vacuum circuit breaker
JGGY vacuum circuit breakers are of the 12KV/24KV/36KV VS1, VJG, VSG series and are used in all typical switching applications such as industrial networks and medium voltage distribution, ranging from short circuit currents and switching loads to busbar sections or connecting networks. Their robust construction including minimal depth and width dimensions will help reduce the need for different panels.
Therefore, these circuit breakers are available with optional earthing switches for plug-in and fixed installations. The main features of this circuit breaker are as follows.
1. The installation in the air-insulated medium-voltage switchgear is very simple
2. High reliability
3. Compact design
4. Remote switching via remote control
5. Low planning costs
6. Long service life
7. Simple maintenance
JGGY Electrical mainly specializes for 6~42kV medium voltage electric (outdoor and indoor): load break switch, Disconnector, cutout fuse, Surge Arrester, vacuum circuit Breaker, ..
several years, with the strength, with good quality and pretty competitive price. Should you have any questions, pls do not hesitate to contact me.
Ms Miya: sales@jggyelectrical.com
Whatsapp: +86 181 0679 6660
