SF6 Micro-Water Density Transmitter: Protecting Power Equipment's Safe Operation

In power systems, the stable operation of SF6 gas equipment is a critical safeguard for grid security. The SF6 micro-water density transmitter, as a core monitoring device, utilizes multi-parameter fusion monitoring and intelligent compensation technology to provide comprehensive protection for the insulation performance and operational reliability of equipment.

This transmitter is specifically designed for medium- and high-voltage power applications and can accurately capture four key parameters in real-time: the density, micro-water content (dew point), pressure, and temperature of SF6 gas within a sealed container. Its core advantage lies in the built-in intelligent compensation algorithm, which automatically converts real-time pressure into equivalent density values at a standard temperature of 20°C, completely eliminating the interference of environmental temperature fluctuations on measurement results. This ensures that the density monitoring accuracy is within ±1.0% FS. Additionally, the micro-water detection covers a dew point range of -50°C to +20°C (Td), allowing for the rapid detection of excessive moisture that could lead to insulation risks. This provides precise data support for the condition assessment of equipment such as GIS (Gas-Insulated Switchgear), circuit breakers, and transformers.

The device is housed in a fully sealed stainless steel casing with an IP65 protection rating, allowing it to operate stably in environments ranging from -40°C to +80°C and with humidity levels up to 95% RH. The helium leakage rate is as low as aerospace-grade standards (≤1×10⁻⁹ Pa·m³/s), ensuring reliable operation in harsh conditions, including outdoor dust, rain, and extreme temperature variations. The modular design supports G1 standard threaded gas interfaces and M12 circular electrical connectors, making it a direct replacement for traditional density meters. It seamlessly adapts to the differential monitoring needs of medium-voltage switchgear (10kV) to ultra-high-voltage GIS (1000kV) equipment. Through RS485 digital signal output (Modbus RTU protocol), the transmitter can be integrated in real-time with power monitoring systems (SCADA), enabling graded warnings and equipment lockout when gas density drops (e.g., below 95% of the rated value) or dew point exceeds the threshold (e.g., >-30°C Td), thereby building an intelligent operation and maintenance system.

In practical applications, the transmitter simplifies the wiring and installation complexity of medium- and high-voltage equipment monitoring systems, especially for the intelligent retrofit of older substations, thanks to its compact structure and multi-parameter fusion capabilities. Its customizable range (0~1.4 MPa abs., expandable) and ±0.5% FS pressure measurement accuracy meet the installation demands of compact spaces in pole-mounted switches while also ensuring high-reliability monitoring for ultra-high-voltage GIS busbars. This makes it an essential "electronic sentinel" for power equipment condition monitoring and maintenance.

With its high-precision measurement, strong environmental adaptability, and intelligent linkage features, the SF6 micro-water density transmitter breaks through the limitations of traditional single-function instruments. By integrating gas density and micro-water content monitoring, it establishes a comprehensive protection system for SF6 insulation equipment, encompassing "leakage warning - insulation assessment - condition management". Its technical advantages and engineering value make it an indispensable core component in the intelligent upgrade of modern power systems, providing solid protection for the safe and stable operation of power grids.

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