LW30-72.5 Outdoor High-Voltage SF6 Circuit Breaker
LW30-72.5 Outdoor High-Voltage SF6 Circuit Breaker is designed for 72.5kV high-voltage power transmission and substation applications. It adopts SF6 gas as the arc-extinguishing and insulation medium, combined with advanced self-energy arc-extinguishing technology and a reliable spring operating mechanism. The circuit breaker features excellent breaking capability, stable insulation performance, and long mechanical service life, making it suitable for transmission lines, substations, capacitor bank switching, and other demanding outdoor power system applications.
Get a QuoteOverview
The LW30-72.5 outdoor SF6 circuit breaker is designed for 72.5kV high-voltage transmission systems and substation applications. Available in both tank-type and porcelain post configurations, it adopts advanced self-energy arc-extinguishing technology combined with a high-reliability mechanical operating system.
With excellent interrupting performance, stable insulation capability, and long mechanical service life, the LW30-72.5 provides reliable switching and protection for medium- and high-voltage power networks. It is particularly suitable for demanding switching applications, including capacitor bank switching and other high-frequency operating conditions.
Operating Conditions
1. Ambient Temperature: –40°C to +55°C;
2. Altitude: Up to 3000m;
3. Wind speed: ≤35 m/s;
4. Ice Thickness: ≤20mm;
5. Seismic: Up to 9° intensity;
6. Pollution Level: III (outdoor, humid, dust, ice-prone areas).
Features
Self-Energy Arc Extinguishing Technology
The LW30-72.5 utilizes a self-energy arc-extinguishing system based on the combination of thermal expansion and auxiliary gas flow. During interruption, the energy generated by the arc is effectively utilized to accelerate SF6 gas expansion, while the auxiliary blowing effect enhances arc cooling and extinction.
The optimized arc contact structure and electric field distribution design incorporate shielding measures on the contact fingers, ensuring uniform electric field distribution and improving dielectric performance.
The split-type gas cylinder structure makes efficient use of arc energy during the interruption process, reducing required operating force while minimizing the risk of restriking.
The circuit breaker features fast dielectric recovery capability, enabling reliable switching of capacitor banks under transient recovery voltage conditions.
High-Reliability Operating Mechanism
The LW30-72.5 is equipped with a CT26 fully spring operating mechanism. The optimized energy transmission design directly transfers energy from the closing mechanism to the tripping spring, reducing mechanical transmission losses and improving operating efficiency.
The oil-free and gas-free operating mechanism design simplifies maintenance requirements, improves environmental adaptability, and meets the development requirements of modern high-voltage switching equipment.
Technical Data
Electrical & Mechanical Specifications
| Item | Unit | Parameter |
| Rated Voltage | kV | 72.5 |
| Rated Current | A | 1600 – 4000 |
| Rated Frequency | Hz | 50 / 60 |
| Rated Short-Circuit Breaking Current | kA | 25 – 40 |
| Electrical Life | / | Excellent, supports repeated high-current switching |
| Mechanical Life | Time | 10000 |
| Operating Sequence | / | O – 0.3s – CO – 180s – CO; full operation within 3 cycles |
| Opening / Closing Time | Rapid response, ≤3 cycles | |
| Transmission Mechanism | Single-side drive; integrated spring & buffer; short transmission chain |
SF₆ Gas & Sealing
| Parameter | Specification |
| Rated Gas Pressure (20°C) | ~0.4MPa |
| Sealing Method | Double O-ring + sealant |
| Annual Leakage Rate | Strictly controlled, very low risk |
Overall and mounting dimensions(mm)
Structure and Material Design
The LW30-72.5 SF6 circuit breaker features an optimized structural design available in both tank-type and porcelain post configurations. The three phases are mechanically linked and installed on a welded base frame, providing a compact layout, high structural strength, and convenient transportation and installation.
Robust Enclosure and Material Selection
The main enclosure is manufactured from corrosion-resistant aluminum alloy, providing excellent durability for outdoor operating environments. The operating mechanism box adopts stainless steel construction to improve protection against moisture, corrosion, and harsh weather conditions.
The fastening components are treated with hot-dip galvanization, enhancing corrosion resistance and ensuring long-term mechanical reliability.
Reliable Sealing and Transmission System
The flange connection adopts a dual-sealing structure, combining water resistance and SF6 gas sealing performance to maintain reliable insulation conditions and prevent leakage.
The optimized single-side transmission design features a shorter mechanical drive path, reducing transmission losses, improving operating efficiency, and lowering mechanical wear during long-term operation.
Typical Applications
The LW30-72.5 SF6 circuit breaker is widely applied in high-voltage power transmission and distribution systems, including substations, transmission lines, and renewable energy grid connection projects.
It is suitable for various applications such as 750kV, 550kV, and 330kV substation systems, power transmission and distribution networks, and large-scale wind and photovoltaic power generation facilities.
The circuit breaker can also be used for capacitor bank switching applications, new substation construction projects, and the modernization or replacement of existing substations. With its reliable outdoor performance and low maintenance requirements, it is especially suitable for remote installations and areas where maintenance resources are limited.
Key Advantages
Advanced Self-Energy Arc Extinguishing Technology
The LW30-72.5 adopts self-energy arc-extinguishing technology to achieve rapid and reliable current interruption. The optimized arc-extinguishing process improves switching safety and reduces interruption stress on connected power equipment.
High Reliability with Low Operating Energy
The optimized operating mechanism reduces required operating force while maintaining excellent mechanical endurance and electrical performance. This design enables stable operation over a long service period with reduced maintenance requirements.
Compact and Weather-Resistant Structure
The circuit breaker features a compact structural design with corrosion-resistant materials and reliable sealing technology. It provides excellent resistance against harsh outdoor conditions, including strong wind, icing, seismic environments, and pollution.
Excellent Dielectric Recovery Performance
With fast dielectric recovery capability and effective restrike suppression, the LW30-72.5 ensures reliable switching performance under demanding operating conditions, including capacitor bank switching.
Extended Maintenance Interval
The reliable SF6 insulation system and durable mechanical structure significantly reduce routine maintenance requirements. Under suitable operating conditions, the maintenance interval can reach up to 10 years.
