1. Structural Overview
The VS1 vacuum circuit breaker is typically composed of five major units:
| Component | Function |
|---|---|
| Vacuum interrupter | Performs arc extinction during switching |
| Operating mechanism | Provides stored energy for opening/closing |
| Insulating support structure | Dielectric insulation for live parts |
| Main contacts & moving shaft | Transfers motion from mechanism to interrupter |
| Chassis / Truck base (for withdrawable type) | Enables installation inside switchgear panel |
The interrupter is sealed at a high vacuum level (10⁻⁶ torr), preventing oxidation and eliminating the need for arc-quenching gas. This is the core feature that allows VS1 to operate safely without environmental leakage or refilling, unlike SF₆ switchgear.
2. Operating Principle
When the breaker opens under load, the contacts separate and an arc forms in the vacuum chamber. Due to the absence of ionized gas, the arc is rapidly stretched and extinguished in less than 10 milliseconds. The dielectric strength of the vacuum recovers instantly, preventing re-ignition. This makes vacuum arc interruption extremely safe, clean, and energy efficient.
When closing, the stored-energy mechanism releases a spring or magnetic force to rapidly re-engage the contacts. Because of the metal bellows and rigid structure of the interrupter, the VS1 VCB achieves mechanical endurance of 30,000 operations or more, well above oil and gas breaker life cycles.
3. Key Technical Parameters
| Parameter | Typical Value |
|---|---|
| Rated voltage | 12kV / 24kV |
| Rated current | 630A – 3150A |
| Rated short-circuit breaking capacity | 20kA / 25kA / 31.5kA |
| Mechanical endurance | 10,000 – 30,000 operations |
| Standards | IEC 62271-100 / GB 1984 |
4. Types of VS1 Breakers
✅ Fixed type – bolted inside switchgear, lower cost
✅ Withdrawable type – mounted on a truck that slides for maintenance
✅ Embedded pole version – resin-molded interrupter for strong insulation
✅ Permanent magnet mechanism type – maintenance-free, ideal for smart grid
5. Why VS1 VCB Is Widely Used
No gas leakage or refilling required
Excellent arc-quenching ability
Long life, low maintenance cost
Compact design for metal-clad switchgear
High reliability in frequent switching duty
Compliant with global grid standards
6. Common Application Fields
✔ 10kV distribution substations
✔ Industrial MCC and power control rooms
✔ Wind and solar energy substations
✔ Mining and tunnel power systems
✔ Data centers and hospitals (critical power load)
✔ Urban grid ring networks (RMU + GIS integration)
Because it is modular and interchangeable, VS1 also supports OEM production, making it one of the most exported medium-voltage breakers from China to Southeast Asia, Africa, South America, Eastern Europe, and the Middle East.
