LW8(A)-40.5 Outdoor AC SF6 Circuit Breaker – Technical Description The LW8(A)-40.5 is a high-performance outdoor AC SF6 circuit breaker designed for medium-voltage power distribution systems, typically rated at 40.5 kV. It utilizes sulfur hexafluoride (SF6) gas as the insulating and arc-quenching medium, ensuring reliable interruption of short-circuit currents and stable operation under harsh environmental conditions. Key Features 1. SF6 Gas Insulation & Arc Extinction The breaker employs SF6 gas for superior dielectric strength and thermal stability. During fault interruption, the gas rapidly extinguishes arcs by absorbing free electrons, minimizing contact erosion and extending service life. The sealed design prevents gas leakage, maintaining consistent performance. 2. Rated Parameters - Rated Voltage: 40.5 kV - Rated Current: Up to 2000 A (depending on configuration) - Short-Circuit Breaking Current: 25 kA–31.5 kA - Mechanical Endurance: 10,000 operations 3. Robust Outdoor Design The LW8(A)-40.5 is built for outdoor installation, featuring a weatherproof enclosure resistant to UV radiation, rain, dust, and extreme temperatures (-30°C to +40°C). The corrosion-resistant housing ensures long-term reliability in coastal or industrial environments. 4. Spring-Operated Mechanism Equipped with a high-speed spring-operated mechanism, the breaker ensures rapid opening/closing (≤60 ms). The energy-stored spring reduces dependency on external power, enhancing fault response reliability. 5. Low Maintenance & Environmental Adaptability The sealed SF6 gas system eliminates the need for frequent maintenance. Self-lubricating bearings and stainless-steel components reduce wear. The breaker complies with IEC 62271 standards for safety and performance. 6. Modular & Flexible Configuration Supports integration with disconnectors, earthing switches, and CT/PT modules for substation automation. Can be retrofitted into existing switchgear or used in new installations. Applications - Transmission & Distribution Networks: Substations, renewable energy grids. - Industrial Plants: Mining, steel, chemical facilities requiring high fault tolerance. - Railway & Infrastructure: Catenary power supply systems. Advantages - High Breaking Capacity: Efficiently interrupts severe fault currents. - Compact Footprint: Saves space compared to oil or vacuum breakers. - Eco-Friendly: SF6 gas has minimal ozone depletion potential (ODP). Conclusion The LW8(A)-40.5 SF6 circuit breaker combines advanced arc-quenching technology, rugged construction, and low maintenance for critical power infrastructure. Its adaptability to extreme conditions makes it a preferred choice for modern medium-voltage applications. (Note: Specifications may vary based on regional standards and customization.)