ZN63(VS1)-12 Indoor High Voltage Vacuum Circuit Breaker
ZN63(VS1)-12 series indoor vacuum circuit breaker is a three-phase AC 50Hz indoor switchgear device with rated voltage of 12kV, designed for control and protection of industrial and mining enterprises, power plants, substations, and electrical facilities, as well as for applications requiring frequent switching operations. It adopts an integrated VET spring-operated operating mechanism and circuit breaker design, and can be used either as a fixed installation unit or equipped with a special draw-out carriage to form a withdrawable (hand-cart) unit for use in metal-clad switchgear such as KYN28-12 series.
The vacuum interrupter utilizes a high-reliability axial magnetic field (AMF) contact structure, which distributes the switching arc uniformly across the contact surface, significantly reducing contact erosion and enabling high breaking capacity with extended electrical service life.
Technical Specifications
| Item | Specification |
|---|---|
| Rated Voltage | 12kV |
| Rated Insulation Voltage | 12kV |
| Rated Frequency | 50Hz / 60Hz |
| Rated Current | 630A / 1250A / 1600A / 2000A / 2500A / 3150A (selectable) |
| Rated Short-circuit Breaking Current | 25kA / 31.5kA / 40kA |
| Rated Short-circuit Making Current | 63kA / 80kA / 100kA (peak) |
| Rated Short-time Withstand Current (Icw) | 25kA / 31.5kA / 40kA (4s) |
| Rated Peak Withstand Current (Ipk) | 63kA / 80kA / 100kA |
| Rated Operating Sequence | O-0.3s-CO-180s-CO (standard) |
| Mechanical Endurance | ≥ 30,000 operations |
| Electrical Endurance | ≥ 100 times rated short-circuit breaking / ≥ 10,000 times rated current breaking |
| Contact Structure | Axial magnetic field (AMF) — copper-chromium (Cu-Cr) alloy |
| Vacuum Interrupter | Sealed for life — no maintenance required |
| Operating Mechanism | VET series spring-operated mechanism (manual or motor-charged) |
| Mechanism Mechanical Life | ≥ 30,000 operations |
| Motor-charging Time | ≤ 15 seconds |
| Degree of Protection | IP2X (enclosure) / IP4X (panel front) |
| Installation Type | Fixed (chassis) or Withdrawable (hand-cart unit) |
| Standards | GB 1984, IEC 62271-100 |
Key Features
- Integrated VET Spring Operating Mechanism: The VET series spring mechanism is directly integrated with the circuit breaker pole assembly, eliminating coupling components between the operating mechanism and vacuum interrupter for a more compact, reliable design — the spring-charging motor provides automatic recharging within 15 seconds after each closing operation, enabling rapid re-closing sequences
- Vacuum Arc Extinction Technology: The vacuum interrupter utilizes sealed-for-life vacuum interrupters with Cu-Cr (copper-chromium) alloy axial magnetic field (AMF) contacts — the AMF contact design distributes the switching arc uniformly across the contact surface, minimizing contact erosion and enabling reliable interruption of high short-circuit currents while maintaining exceptionally long electrical service life exceeding 10,000 rated current operations
- High Mechanical Endurance: Rated for 30,000 mechanical operations and 10,000 rated current breaking operations — significantly exceeding the industry standard of 10,000 mechanical operations, making the ZN63(VS1)-12 suitable for the most demanding frequent-operation applications such as arc furnace switching, capacitor bank switching, and motor starting duty
- Dual Installation Flexibility: Can be supplied as a fixed-mounting unit for stand-alone installation in fixed-type switchgear, or as a withdrawable hand-cart unit with automatic secondary disconnect contacts for use in KYN28-12 and similar metal-clad withdrawable switchgear — the hand-cart version features smooth roll-out on wheeled carriages with Connected/Test/Disconnected positions
- Sealed-for-Life Vacuum Interrupter: The vacuum interrupter is hermetically sealed at the factory and requires no maintenance, gas monitoring, or replacement of arc-extinguishing media over the full service life — eliminating the environmental and operational concerns associated with SF6 gas circuit breakers and reducing lifetime maintenance costs
- Comprehensive Mechanical Interlocking: Integrated interlocks prevent incorrect operations including: preventing closing when the mechanism is not fully charged, preventing opening of the front panel when the breaker is in the closed position, and ensuring correct position interlocking in withdrawable configurations
- Proven Field Performance: The VS1 mechanism platform is one of the most widely deployed medium voltage vacuum circuit breaker operating mechanisms in China, with hundreds of thousands of units in reliable service across power generation, distribution, and industrial applications
Applications
- Power plants — generator outlet, auxiliary power switching
- Substations — 6kV/10kV incoming, outgoing, and bus-riser switching
- Industrial and mining enterprises — motor control and process power
- Commercial buildings — medium voltage main switchboards
- Infrastructure — airports, hospitals, data centers
- Frequent operation applications — capacitor bank switching, arc furnace control
- Metal-clad withdrawable switchgear (KYN28-12 series) — as the main switching device