High-voltage transmission systems require switching equipment that can safely interrupt heavy fault currents while maintaining long-term operational stability. The SF6 Gas Circuit Breaker is widely used in transmission substations, power plants, renewable energy facilities, and industrial power networks due to its excellent insulation performance and reliable arc extinguishing capability.
Designed for high-voltage applications, our SF6 circuit breaker range combines advanced gas interruption technology, robust mechanical structures, and intelligent monitoring functions. The 126KV SF6 Circuit Breaker provides dependable protection for urban and regional substations, while the 126kV Outdoor SF6 Breaker is engineered for long-term outdoor operation under harsh weather conditions.
For demanding transmission applications, the 126KV High Voltage SF6 Circuit Breaker delivers high short-circuit interruption capability, while the proven LW36-126 SF6 Circuit Breaker integrates mature mechanical design with reliable field performance.
The operating principle of an SF6 Gas Circuit Breaker is based on the superior dielectric strength and thermal conductivity of sulfur hexafluoride gas. During normal operation, the breaker maintains current flow through closed contacts. When a fault occurs, the operating mechanism rapidly separates the contacts and creates an arc.
During the opening process, compressed SF6 gas is directed through a specially designed nozzle into the arcing zone. The high-speed gas flow cools and de-ionizes the arc, allowing the current to be safely interrupted when it reaches zero crossing. After interruption, the high dielectric recovery strength of SF6 prevents arc re-ignition and ensures reliable isolation.
This puffer-type interruption technology enables stable performance for high-voltage switching applications, including transformer protection, transmission line switching, and short-circuit fault clearing.
The SF6 Gas Circuit Breaker is commonly selected for applications where high reliability and fast fault interruption are essential.
The SF6 Gas Circuit Breaker adopts a sealed interrupter chamber combined with a reliable operating mechanism to achieve stable switching performance. Depending on project requirements, both live-tank and dead-tank configurations are available.
| Parameter | Specification |
|---|---|
| Rated Voltage | 126 kV |
| Rated Frequency | 50 / 60 Hz |
| Rated Current | 2000 A (630A–3150A optional) |
| Rated Short-Circuit Breaking Current | 40 kA |
| Short-Time Withstand Current | 40 kA / 3 seconds |
| SF6 Gas Pressure at 20°C | 0.5 MPa (gauge) |
| Opening Time | ≤40 ms |
| Closing Time | ≤150 ms |
| Mechanical Endurance | M2 Class, 10,000 CO operations |
| Electrical Endurance | 20 full short-circuit interruptions |
| Control Voltage | 110V / 220V DC |
| Protection Degree | IP55 |
| Operating Temperature | -40°C to +50°C |
| Creepage Distance | ≥25 mm/kV |
| Applicable Standard | IEC 62271-100 |
To ensure long-term reliability, every unit undergoes comprehensive factory testing before shipment. The testing process includes dielectric withstand testing, mechanical operation verification, partial discharge measurement, and SF6 gas leakage inspection according to IEC 62271-100 requirements.
| Comparison Item | SF6 Gas Circuit Breaker | Vacuum Circuit Breaker |
|---|---|---|
| Arc Extinguishing Medium | SF6 Gas | Vacuum |
| Main Application | High voltage transmission systems | Medium voltage distribution systems |
| Breaking Capacity | Excellent for high fault currents | Excellent for medium voltage applications |
| Installation | Substations and transmission networks | Distribution panels and compact switchgear |
| Maintenance | Low maintenance with gas monitoring | Very low maintenance |
As an experienced electrical equipment manufacturer, we provide complete SF6 circuit breaker solutions including engineering support, customized configurations, technical documentation, and after-sales service.
Q1: What is an SF6 Gas Circuit Breaker used for?
It is mainly used in high-voltage transmission systems, substations, and industrial power networks for reliable fault interruption and circuit isolation.
Q2: Why is SF6 gas used in circuit breakers?
SF6 gas has excellent insulation strength and arc extinguishing capability, making it suitable for high-voltage switching applications.
Q3: What standards do SF6 circuit breakers comply with?
Most high-voltage SF6 circuit breakers are designed according to IEC 62271-100 standards.
Q4: How long is the service life of an SF6 circuit breaker?
With proper maintenance and installation, SF6 circuit breakers can provide more than 30 years of reliable operation.