MGS24-SF6 Sensor: SF6 Gas Detection Technology and Performance Analysis

1. Introduction to SF6 Gas

SF6 is chemically stable, does not decompose at temperatures between 500°C and 600°C, and is unreactive with acids, alkalis, salts, ammonia, and water. Under the influence of an electric arc (at several thousand degrees Celsius), it decomposes into sulfur and fluorine atoms. Once the arc is released, these atoms recombine to form SF6.

SF6 exhibits excellent electrical insulation properties and arc-extinguishing performance. Its dielectric strength is 2.5 times that of fluorine gas at the same pressure, its breakdown voltage is 2.5 times that of air, and its arc-extinguishing capacity is 100 times that of air. It is a new generation of high-voltage insulating dielectric material that outperforms both air and oil.

2. Applications of SF6 Gas

Since the mid-1960s, SF6 has been widely used as an insulating medium in high-voltage electrical equipment. SF6 gas-insulated, fully enclosed switchgear occupies a small footprint and is resistant to environmental interference, making it suitable for ultra-high voltage systems and distribution networks. SF6 gas-insulated pipeline transmission lines offer low dielectric loss, high capacity, and can be used in high-rise locations. They are therefore often used in hydropower station outgoing lines, replacing conventional oil-filled cables. SF6 gas-insulated transformers are fire- and explosion-resistant, making them suitable for power supply in densely populated areas and high-rise buildings.

SF6 is non-toxic, but its density is approximately five times that of air. Leaks of SF6 easily accumulate in low-lying areas (such as cable trenches), and high concentrations can cause asphyxiation, necessitating ventilation. The decomposition products of SF6 (such as SF4 and HF) produced by arcing are highly corrosive and toxic, making the installation of SF6 gas leak monitoring equipment highly desirable in power plants.

As a core component of gas leak monitoring equipment, SF6 sensors play a decisive role in the equipment's detection capabilities. Therefore, when selecting appropriate SF6 gas leak monitoring equipment, it's important to consider the performance of the SF6 sensor.

3. Principles of SF6 Detection Technology

Currently, mainstream detection technologies on the market include ultraviolet ionization, infrared (NDIR), electrochemical, ultrasonic, and semiconductor technologies. A comparison of their advantages is shown below:

Comparisons show that UV ionization technology is susceptible to dust interference and is relatively expensive; ultrasonic and semiconductor technologies, while low-cost, are prone to false alarms; and electrochemical methods, while relatively inexpensive, suffer from poor stability and a short lifespan. However, infrared (NDIR) technology excels in stability, sensitivity, and lifespan, combined with low requirements for field environments and low development costs, making it the preferred method for SF6 gas concentration detection.

 4. Advantages of the MGS24-SF6 Gas Sensor

MFrontier MGS24-SF6 sensor

MFrontier MGS24-SF6 sensor uses the NDIR (Non-Dispersive Infrared) measurement principle.

NDIR technology schematic

In addition, the MGS24-SF6 sensor uses a gold-plated gas chamber and high-precision sampling circuit, with built-in temperature compensation and pressure compensation functions, which further improves detection accuracy and anti-interference capabilities, while reducing environmental impact. It can more accurately measure the gas concentration of SF6 in the environment, and has the advantages of long service life, high measurement accuracy, good gas selectivity, and stable performance.

5. MGS24-SF6 gas sensor parameters