Vacuum circuit breakers are medium and high voltage switchgear that use vacuum as arc extinguishing medium and insulating medium. They are widely used in power systems, medium and high voltage distribution systems, industrial electricity, rail transit and electrified railways, commercial buildings and data centers.
1. Vacuum arc extinguishing chamber (core component)
Function:
Arc extinguishing: When the circuit breaker is opened, the arc generated between the contacts is quickly extinguished in a vacuum environment (above 10⁻⁴ Pa), which is achieved by diffusion and cooling after ionization of metal vapor.
Insulation: The high insulation strength of vacuum (about 10 times that of air) ensures reliable insulation between contacts after opening.
Composition:
Contact material: usually copper-chromium alloy (CuCr), resistant to arc erosion and good conductivity.
Shielding cover:
Main shielding cover: prevents metal vapor from condensing on the insulating shell and maintains insulation strength.
Equalizing shielding cover: improves electric field distribution.
2. Operating mechanism
Function: provide power for opening and closing, and maintain the contact state.
Common types:
Spring operating mechanism: use spring energy storage, reliable operation, less maintenance.
Electromagnetic operating mechanism: driven by electromagnet, simple structure but high energy consumption.
Permanent magnet operating mechanism: permanent magnet retention, electronic control, long life, fast action.
3. Insulating support
Function:
Common materials are ceramic or epoxy resin (with high mechanical strength and insulation properties).
4. Conductive circuit
Function: conduct normal working current, including:
Inlet and outlet terminals: connect the main circuit.
Conductive rod: connect the interrupter contact to the external line.
5. Buffer device
Function:
Absorb the mechanical impact force during the opening and closing process, and protect the interrupter and operating mechanism.
Common types: hydraulic buffer or spring buffer.
6. Auxiliary components
Position indicator: displays the circuit breaker open/closed state.
Auxiliary contacts: used for control circuit signal transmission (such as interlocking, alarm).
Anti-jump device: prevents the circuit breaker from repeatedly closing and closing in the event of a fault.
Advantages of vacuum circuit breakers
Long life: small contact wear and mechanical life of up to tens of thousands of times.
Environmental protection: no oil or SF₆gas, no risk of explosion or greenhouse effect.
Typical application scenarios
Medium and high voltage power distribution systems (6kV~40.5kV).
Occasions where fault current needs to be quickly cut off (such as substations, industrial electricity).
Through the coordinated work of various components, vacuum circuit breakers achieve efficient and reliable circuit breaking and protection functions.
VTZ-12 vacuum circuit breaker produced by Shaanxi West Power Tongzhong Electrical Co., Ltd. is an indoor switchgear for rated voltage 12kV, AC 50/60Hz. It adopts a modular operating mechanism and is suitable for various industrial and mining enterprises, as well as power grid equipment. It can be used as a handcart unit for use with KYN28A-12 switchgear, or as a fixed unit with relevant mechanical interlocking, making it suitable for XGN2 and other fixed cabinets.
VTZ-12 vacuum circuit breaker has many advantages:
1.Convenient maintenance:
the modular mechanism design allows for easy replacement of the closing and opening coils without the need for dismantling other components. This eliminates the need for testing or adjustment after replacement, ensuring users to replace them independently, making subsequent maintenance more convenient.
High conductivity performance:
the product features a well-designed conductive circuit that meets 1.1 times the rated current temperature rise level.
2.Wide application range:
the product series has a wide application range, rated currents from 630A to 5000A, and rated breaking currents from 20kA to 50kA. It is suitable for all environments within an altitude of 4500 meters and an operating temperatures from -40°C to 40°C.
Supports intelligent customization:
a. It can add a wireless temperature monitoring solution with self-powered design to ensure safety and maintenance-free operation.
b. It has a mechanical characteristics monitoring solution to provide real-time monitoring of circuit breaker operating data for early detection and resolution of potential problems.
c. It has a motorized cabinet entry solution to allow remote operation for ensuring personal safety.
d. Real-time component aging can be detected by partial discharge testing.
Shaanxi West Power Tongzhong Electrical Co., Ltd.
Contact: Ms.Grace Liu (Director of Sales Department)
Tel: +86 917 3661109 Fax: +86 917 6739416
Mobile: +86 18091765882(WhatsApp/Wechat/skype )
Website:https://www.xdtzelectrical.com
