Indoor High-Voltage SF6 Circuit Breaker 40.5kV

Product Overview
The SFM-40.5 Series Indoor High-Voltage SF6 Circuit Breaker is a high-performance switching device designed for indoor medium and high-voltage power systems. Leveraging advanced SF6 gas insulation and arc-extinguishing technology, it delivers exceptional reliability, safety, and adaptability, making it an ideal core component for power grids, industrial facilities, and large-scale infrastructure projects worldwide.With customized solutions for high-altitude environments (up to 4000m) and wide compatibility with mainstream switchgear models, this circuit breaker meets the diverse needs of global purchasers, especially those with demanding environmental and installation requirements. It is engineered to ensure stable operation in harsh conditions while simplifying on-site installation and maintenance.

Operating Conditions

The SFM-40.5 Series is designed to adapt to a wide range of indoor operating environments, with optional customization for extreme conditions, fully meeting the needs of overseas projects in different regions:

• Altitude: ≤2000m (standard); customized high-altitude version available for up to 4000m (with upgraded insulation performance)
• Ambient Temperature: -25°C ~ +40°C, suitable for both cold and warm climate zones
• Relative Humidity: Monthly average ≤90%; daily average ≤95%
• Water Vapor Pressure: Monthly average ≤1.8kPa; daily average ≤2.2kPa, resistant to condensation
• Seismic Resistance: Up to 8 degrees, applicable to earthquake-prone regions
• Electromagnetic Interference (EMI): Withstands EMI up to 1.6kV in secondary systems, ensuring stable electrical performance
• Installation Site: Indoor areas free from flammable, explosive, severe pollution, chemical corrosion, and severe vibration

Structural Features 

• No Operational Overvoltage: Combines the inherent properties of SF6 gas with advanced arc-blowing technology, eliminating restrikes and operational overvoltage, thus protecting downstream electrical equipment from damage.
• Excellent Mechanical Performance: Equipped with CT100 operating mechanism, featuring compact layout and simple structure, with a mechanical service life of up to 10,000 operations, reducing maintenance frequency and lifecycle costs.
• Easy & Lightweight Operation: Adopts lead screw and nut propulsion device, allowing easy movement within switchgear cabinets, simplifying on-site installation, debugging, and maintenance.
• Superior Insulation Performance: Meets the requirements of high-altitude, condensation, and Class II pollution environments, ensuring reliable operation in harsh indoor conditions without insulation failure.
• Strong Corrosion Resistance: Mechanism components adopt advanced processing technology, enhancing wear resistance and corrosion resistance, ensuring long-term reliable operation even in harsh industrial environments.
• High Versatility: Complete switchgear matching solutions, compatible with mainstream models such as KYN61-40.5, JYN-40.5, GBC-40.5, XGN17-40.5, eliminating compatibility issues for retrofit and new projects.

Key Technical Highlights

Application Scenarios

With its strong environmental adaptability and high versatility, the SFM-40.5 Series is widely used in global 40.5kV indoor power systems, particularly suitable for:

• Power Grid Infrastructure: Indoor substations, distribution stations, and power transmission and distribution systems, ensuring stable and safe operation of the power grid.
• Industrial Facilities: Factories, mines, smelters, and industrial parks with demanding power requirements, protecting heavy machinery and production lines.
• High-Altitude Projects: Customized high-altitude version (up to 4000m) for power systems in mountainous regions and high-elevation areas worldwide.
• Commercial & Public Facilities: Large shopping malls, office buildings, hospitals, and data centers, providing reliable power protection for critical loads.
• Switchgear Retrofits: Compatible with mainstream switchgear models, serving as a cost-effective upgrade for legacy power systems, reducing replacement costs.
• International EPC Projects: Compliant with international standards, suitable for overseas engineering, procurement, and construction projects, meeting regional technical and environmental requirements.