Overview
The ZW32-12(G) outdoor pole-mounted high-voltage vacuum circuit breaker is engineered for 12kV, 50Hz overhead power distribution systems in both urban and rural networks. It reliably interrupts load currents, overload currents, and short-circuit currents while enhancing grid stability, safety, and readiness for automation.
Featuring a three-phase outdoor post structure, the ZW32-12(G) offers a compact, lightweight, and maintenance-free design that ensures long service life with fire- and explosion-free operation. Its robust construction delivers exceptional reliability under harsh environmental conditions, making it ideal for smart grid applications and remote distribution networks.
Key Ratings Snapshot
| Parameter | Value |
|---|---|
| Rated Voltage | 12 kV |
| Rated Current | 630 A |
| Rated Short-Circuit Breaking Current | 20 kA |
| Rated Short-Time Withstand Current | 20 kA/4s |
| Rated Peak Withstand Current | 50 kA |
| Power Frequency Withstand Voltage | 42 kV/min |
| Lightning Impulse Withstand Voltage | 75 kV (peak) |
| System Frequency | 50 Hz |
| Application | Outdoor, Overhead Distribution |
| Operation Modes | Manual, Electric, Remote |
Model Designation
- Z: Vacuum Circuit Breaker
- W: Outdoor Application
- 32: Design Sequence
- 12: Rated Voltage (kV)
- G: With Isolating Switch
- 630: Rated Current (A)
- 20: Rated Short-Circuit Breaking Current (kA)
Construction
The ZW32-12(G) features a three-phase post structure with fully sealed construction, providing excellent moisture-proof and anti-condensation performance suitable for cold and humid climates. High-quality outdoor-grade insulation materialsâsuch as epoxy resin or silicone rubber-wrapped epoxy resinâare used for posts and current transformers, ensuring resistance to UV exposure, extreme temperatures, and aging.
Its miniaturized spring operating mechanism is low-energy and high-efficiency, with fewer moving parts housed in a sealed mechanism box to prevent rust and ensure stable operation. The unit supports manual, electric, and remote control modes and is compatible with smart controllers and recloser systems. Customizable CT integration allows for two- or three-phase protection CTs, with optional metering CTs available. The G-model includes an integrated three-phase isolating switch with visible disconnection, mechanical interlocks, and support for lightning arresters and post insulators.
Technical Parameters
Service Conditions
- Voltage Class: 12 kV
- Frequency: 50 Hz
- Installation Type: Outdoor, pole-mounted on overhead distribution networks
- Environment: Standard outdoor conditions; suitable for cold, humid, and coastal areas due to sealed design and outdoor-grade insulation
Technical Data
| Rated Voltage (kV) |
Rated Current (A) |
Rated Short-Circuit Breaking Current (kA) |
Rated Short-Time Withstand Current (kA/4s) |
Rated Peak Withstand Current (kA) |
Power Frequency Withstand Voltage (kV/min) |
Lightning Impulse Withstand Voltage (kV, peak) |
|---|---|---|---|---|---|---|
| 12 | 630 | 20 | 20 | 50 | 42 | 75 |
Installation & Wiring
Installation Diagram
The breaker is designed for direct mounting on standard phi190 concrete or steel poles. Proper clearance and alignment during installation are essential to maintain electrical safety and mechanical stability.
Outline Dimensions
| Dimension | Value (mm) |
|---|---|
| Total Height | 1890 |
| Mounting Bracket Height | 1350 |
| Phase Spacing | 300 |
| Pole Diameter Compatibility | phi190 |
Selection & FAQs
Selection Guide
- Confirm a 12kV, 50Hz overhead feeder and verify the 630A current rating against maximum load, ambient conditions and planned capacity.
- Ensure the 20kA breaking and four-second withstand rating exceeds the prospective fault current, with the required 50kA peak duty.
- Select ZW32-12 or ZW32-12G with integrated isolator; define whether manual, electric, remote or automatic-reclosing operation is required.
- Specify two- or three-phase protection CTs, optional metering CTs, ratios, accuracy, burden, controller, auxiliary supply and communication protocol.
- Verify pole type and strength, φ190 compatibility, 300mm phase spacing, wind/ice loads, clearances, surge arresters, grounding and maintenance access.
Frequently Asked Questions
Q1: Which short-circuit breaking capacity does this 12kV vacuum breaker offer?
It provides a rated short-circuit breaking current of 20 kA. Ensure this value exceeds the prospective fault current at your installation point. Contact us for system fault level verification.
Q2: Can this pole-mounted circuit breaker operate in coastal or humid environments?
Yes, it is suitable for outdoor use in cold, humid, and coastal areas. The sealed design and outdoor-grade insulation protect against harsh conditions. Confirm specific IP requirements for your project.
Q3: What are the power frequency and lightning impulse withstand voltages?
The unit withstands 42 kV/min for power frequency and 75 kV peak for lightning impulses. These ratings meet standard 12 kV outdoor distribution network requirements. Request detailed type test reports if needed.
Q4: Are factory acceptance tests performed before shipment?
Standard routine tests are conducted prior to dispatch. Specific customized testing protocols or third-party inspections are subject to confirmation. Please specify your testing requirements during the inquiry stage.
Q5: How long is the lead time for customized orders?
Standard production lead times apply to base models. Customized configurations or specific accessory integrations require extended manufacturing schedules. Contact our sales team for exact delivery timelines based on your order volume.
Q6: Where is this 12kV outdoor vacuum circuit breaker typically applied?
It is primarily used in 12kV, 50Hz outdoor overhead distribution networks. The pole-mounted design makes it ideal for rural and urban grid automation. Verify local grid standards for compliance.
Q7: When should I select this specific 12kV pole-mounted breaker model?
Select this model for 12kV, 50Hz outdoor overhead distribution networks requiring 630A rated current. It provides 20kA short-circuit breaking capacity for standard grid applications. Consult our engineers for specific grid matching.