While the VS1 VCB series has become a standard product in the medium-voltage market, not all models are suitable for all applications. Engineers, EPC contractors, and switchgear manufacturers must evaluate electrical, mechanical, and environmental factors before choosing the correct configuration.

Below is a complete selection guide for the VS1 vacuum circuit breaker.

1. Rated Voltage and System Compatibility

Most VS1 breakers are used in 6kV–12kV power systems, but there are also 24kV versions for higher distribution levels. The breaker must match the system neutral grounding method — insulated, grounded through resistor, or solid-grounded.

2. Rated Current and Load Requirements

Incorrect current selection causes overheating and accelerated contact wear.

3. Short-Circuit Breaking Capacity

VS1 models are available in 20kA, 25kA, and 31.5kA versions. The correct value depends on the fault level of the grid. For renewable/industrial hybrid networks, 31.5kA is recommended due to unpredictable inrush currents.

4. Mechanical Type: Fixed or Withdrawable?

5. Mechanism Options

✅ Spring mechanism – traditional, durable, easy to service
✅ Permanent magnet mechanism (PM) – high-end, zero-maintenance, used in digital substations

6. Environmental Options

• Anti-condensation heaters for humid areas

• High-altitude derating version (≥ 3000m)

• Sand/dust-proof design for desert and mining regions

• Tropical climate corrosion protection coating

7. Certification and Testing Checklist

Before procurement, the VS1 breaker should include:

8. Supplier Selection Factors

• Does the manufacturer provide OEM/ODM customization?

• Are spare parts guaranteed for 10+ years?

• Is after-sales technical support available?

• Can factory inspection or third-party witness testing be arranged?