Overview
The ZW7-40.5kV outdoor high-voltage vacuum circuit breaker is a three-phase AC device rated for 40.5kV and 50Hz systems, engineered for reliable switching and protection in outdoor high-voltage transmission networks. It supports both remote electrical control and local manual operation, making it ideal for automated and conventional power infrastructure.
Designed in full compliance with GB1984 and IEC 62271-100 standards, the ZW7 delivers robust performance under demanding conditions. Its hermetically sealed design ensures excellent resistance to moisture, pollution, and extreme weather, while offering non-flammable, explosion-proof operation with minimal maintenance.
Model Designation
Construction
Featuring a columnar structure integrated with vacuum interrupters and high-strength ceramic or epoxy insulators, the ZW7 excels in environments requiring frequent switching operations. The hermetically sealed design provides excellent resistance to moisture, dust, salt fog, and UV exposure, ensuring stable performance even in harsh outdoor conditions.
Non-flammable and explosion-proof by design, the breaker offers a long service life with compact dimensions and straightforward installationâmaking it well-suited for modern urban, rural, and industrial power systems where reliability and space efficiency are critical.
Technical Parameters
Service Conditions
- Ambient air temperature: -40 degC to +40 degC
- Altitude: <= 2000 meters
- Wind speed: 3.2:10 km/h
- Earthquake intensity: <= Level 8
- Minimum nominal creepage distance: 31 mm/kV
- Air pollution degree: Class IV
Technical Data
| Item | Unit | Data |
|---|---|---|
| Rated Voltage | kV | 40.5 |
| Rated Insulation Level – Power Frequency Withstand Voltage (Dry) | kV | 95 |
| Rated Insulation Level – Power Frequency Withstand Voltage (Wet) | kV | 80 |
| Rated Insulation Level – Lightning Impulse Withstand Voltage (Peak) | kV | 185 |
| Rated Current | A | 1250, 1600, 2000 |
| Rated Short-Circuit Breaking Current | kA | 20, 25, 31.5 |
| Rated Operating Sequence | – | O-0.3s-CO-180s-CO |
| Number of Rated Short-Circuit Breaking Operations | times | 12 |
| Rated Short-Circuit Closing Current (Peak) | kA | 50, 63, 80 |
| Rated Peak Withstand Current | kA | 50, 63, 80 |
| Rated Short-Time Withstand Current | kA | 20, 25, 31.5 |
| Rated Short-Circuit Duration | s | 4 |
| Average Opening Speed | m/s | 1.5 ± 0.2 |
| Average Closing Speed | m/s | 0.7 ± 0.2 |
| Contact Bounce Time | ms | ≤ 2 |
| Opening/Closing Time Difference of Three Phases | ms | ≤ 2 |
| Closing Time | ms | ≤ 150 |
| Opening Time | ms | ≤ 60 |
| Mechanical Life | times | 10000 |
| Rated Operating Voltage & Auxiliary Circuit Rated Voltage | V | DC 220, 110, 24 / AC 220, 110, 24 |
| Resistance of Each Phase Circuit (without CT) | μΩ | ≤ 100 |
| Allowable Wear Thickness of Moving/Static Contacts | mm | 3 |
| Weight | kg | 800 |
Installation & Wiring
Installation Diagram
The ZW7-40.5kV breaker features a modular columnar structure with clearly labeled components for straightforward field assembly and maintenance. Ensure proper clearance and grounding during installation according to local electrical codes.
Outline Dimensions
| Dimension | Value (mm) |
|---|---|
| 1. Upper outgoing terminal | : |
| 2. Vacuum arc-extinguishing chamber | : |
| 3. Handhole cover plate | : |
| 4. Lower outgoing terminal | : |
| 5. Column insulator | : |
| 6. Mechanism box | : |
| 7. Door | : |
| 8. Lifting ring screw | : |
| 9. Door handle | : |
| 10. Mechanism (inside the box) | : |
| 11. Observation window | : |
| 12. Insulated pull rod | : |
| 13. Base | : |
| 14. Support | : |
| 15. Current transformer | : |
| 16. Bolt | : |
Selection & FAQs
Selection Guide
- Confirm a 40.5kV, 50Hz outdoor application and select 1600A or 2000A after evaluating continuous load, temperature rise and environmental derating.
- Choose 25kA or 31.5kA breaking capacity above the prospective fault current and verify matching four-second, peak-making and peak-withstand duties.
- Check 185kV lightning impulse, 95kV dry and 80kV wet one-minute withstand levels against system insulation coordination and surge protection.
- Specify the spring mechanism’s control voltage and coordinate remote/local operation, trip and close circuits, auxiliary contacts, CTs, relays and reclosing logic.
- Verify −40°C to +40°C conditions, Class IV pollution, at least 31mm/kV creepage, foundation, lifting, terminal forces, clearances and grounding.
Frequently Asked Questions
Q1: What is the maximum short-circuit breaking current for this 40.5kV breaker?
The rated short-circuit breaking current is up to 31.5 kA. It also supports a 63 kA or 80 kA peak closing current. Confirm your specific system fault level with our engineering team.
Q2: Can this outdoor vacuum circuit breaker operate in extreme cold and high altitudes?
Yes, it operates in ambient temperatures from -40°C to +40°C and altitudes up to 2000 meters. For installations exceeding these limits, please contact us for custom derating solutions.
Q3: When are type test reports provided during the procurement process?
Standard routine tests are performed prior to dispatch. Full type test reports and specific inspection certificates are available subject to confirmation. Contact our sales team for detailed test documentation.
Q4: Which insulation withstand voltages are supported by this 40.5kV breaker?
The lightning impulse withstand voltage is rated at 185 kV. Additionally, it features 95 kV dry and 80 kV wet power frequency withstand voltages. Verify these insulation levels match your network requirements.
Q5: Are 2000A rated current configurations available for this model?
Yes, the ZW7-40.5kV breaker is available in both 1600A and 2000A rated current configurations. Specify your exact primary current requirement during the inquiry phase for accurate factory quotation.
Q6: Why choose this vacuum circuit breaker for Class IV pollution areas?
It features a minimum nominal creepage distance of 31 mm/kV to prevent flashovers in heavy pollution. This ensures reliable outdoor performance in Class IV environments. Confirm site pollution severity with our engineers.
Q7: How does the rated operating sequence support automatic reclosing operations?
The standard operating sequence is Open – 0.3s – Close-Open – 180s – Close-Open. This ensures reliable auto-reclosing capabilities for transient fault clearing. Confirm the exact sequence timing with our technical department.
Q8: Is the ZW7-40.5kV suitable for outdoor substation protection?
Yes, it is an outdoor high-voltage vacuum circuit breaker designed for 40.5kV AC power systems. It provides reliable control and protection for outdoor substations and industrial networks.