Vacuum circuit breakers are widely used in high-voltage switchgear, leveraging vacuum as the arc-extinguishing and insulating medium within a sealed vacuum container. Since their introduction in the early 1960s, advancements in key processes, the development of new arc chambers, and improvements in operating mechanisms have significantly enhanced their technical parameters. These circuit breakers, known for their excellent performance and reliability, have become increasingly prevalent in high-voltage switchgear applications.

Below is an overview of the advantages and disadvantages of vacuum circuit breakers:

Advantages:

1. Sealed Arc Chamber:
   The arc extinguishes within a sealed container, preventing exposure to arc or hot gases. The arc chamber is designed as a standalone component, making installation and maintenance simple.
2. Compact Contact Gap:
   The contact gap is small (around 10mm), requiring less closing force, simplifying the mechanism, and extending the service life.
3. Efficient Arc Extinguishing:
   With a short arc-extinguishing time, low arc voltage, minimal energy loss, and reduced contact wear, vacuum circuit breakers support numerous switching operations.
4. Low Inertia:
   The lightweight moving guide rod allows for frequent use.
5. Compact and Lightweight Design:
   The operating mechanism is minimal, resulting in a smaller and lighter overall device.
6. Low Power Consumption and Noise:
   Operating the switch requires little control power, and it generates minimal noise during operation.
7. Safety:
   These breakers are oil-free, eliminating the risk of explosion or fire hazards, ensuring safe operation.
8. Durability and Stability:
   The sealed structure prevents performance degradation caused by moisture, dust, or harmful gases, ensuring reliable and consistent operation.
9. Rapid Recovery:
   After the arc is extinguished, the insulating medium between the contacts quickly recovers without needing replacement.
10. Low Maintenance Requirements:
    The components, including the contact ring, do not degrade and require no replacement. Maintenance intervals can extend up to 20 years, and maintenance costs are about 1/20th of those for oil-less circuit breakers.
11. Reclosing Capability:
    Vacuum circuit breakers can handle multiple reclosing operations, making them ideal for distribution network applications.

Disadvantages:

1. Overvoltage Risk:
   Switching inductive or capacitive loads can cause overvoltage due to phenomena like current chopping or re-ignition. Adequate overvoltage protection is necessary.
2. High Initial Cost:
   The specialized production of vacuum interrupters and the reliability of the mechanism result in a higher upfront cost. However, considering long-term operational and maintenance savings, the overall cost-effectiveness is favorable.
3. Contact Bouncing Issues:
   The docking-type contact structure and spring-based operating mechanism may lead to:
   • Closing bounce: Causes high overvoltage, potentially burning or welding the contacts, especially during inrush current or short-circuit closing.
   • Opening rebound: Reduces the post-arc contact gap, risking re-breakdown and severe consequences.

Applications:

Vacuum circuit breakers are predominantly used in indoor high-voltage switchgear, such as 12kV, 24kV, and 36kV VS1 mid-mounted switchgear. They are a critical component in ensuring reliable, safe, and efficient operation within power distribution systems.

Professional vacuum circuit breakers supplier and manufacturer

1. Zhejiang GONGSHUN Electrical Co.,Ltd (electric-cn.com), Our company was founded in the late 1990s, specializing in the production of inflatable cabinets, SF6 inflatable cabinets, and various high and low voltage complete sets of electrical equipment. It has multiple subsidiaries under its jurisdiction, including high-voltage load switch branch, high-voltage circuit breaker branch, high-voltage fuse branch, and technology development branch.Our technical expertise, comprehensive product portfolio and long-term rich experience are helping many customers in need to solve their power problems. We’re happy to help at any time.  Whether you need application product advice or technical assistance, our global service team is committed to providing you with the right support. For more technical information about medium voltage earthing switch, feel free to contact us, send an email to gongshun@electric-cn.com 
2. Our company specializes in producing 12KV-40.5KV series high-voltage electrical products: FZN58, FLN48, FLN36, FZRN25, FZN21, FN18, ZFN16, FN12, FN8, FN7, FN5, XRNT, XRNP, VS1, ZN28, ZW8, ZW32, JN15, GN19, GN22, GN24, GN30, CLXGN15-12, HXGN □ -12, DXG-12 (L), DFW □ -12 high-voltage cable branch box, CLXGN □ -12 (SF6) series inflatable cabinet 12KV and 35KV cable accessories, etc; CLVXP-12 indoor AC high voltage fixed switchgear, CL-SIS-12 compact solid insulated ring main unit, professional assembly Schneider SC6 (SF6) series load switchgear, ABB produced SFG (SF6) series load switchgear and other series products; Distribution and agency of high-voltage load switches and inflatable cabinets produced by Schneider Electric and ABB; Siemens produces the 3AJ1 series of indoor medium voltage vacuum circuit breakers and other related products. The company has a complete range of products and has been operating safely on domestic and international power grids for a long time, receiving unanimous praise from both new and old users. Among them, multiple products such as FZRN25, FN12, FLN36-12, XRNT-12 have been exported to various countries and regions in East Asia, South Asia, Southeast Asia, Africa, and the United States.