Why Does Sulfur Hexafluoride Equipment Use Density Relay Instead of Pressure Gauge?

Introduction to Automatic SF6 Density Relay Calibrator

The Automatic SF6 Density Relay Calibrator is an intelligent fully automatic instrument for calibrating SF6 density relays. Using single cycle instruction microcomputer technology, the operating speed is 10 times that of ordinary single chip microcontrollers. It can perform on-site calibration of pointer contact output and intelligent current output SF6 density relays. Real-time capture of the action of the density relay is achieved through interrupt mode, making the instrument measurement more accurate and timely.

Why SF6 Density Relays are used in SF6 Equipment?

According to the ideal gas state equation: pv=nRT, it can be seen that pressure p is linearly related to temperature. When the gas temperature changes in SF6 equipment, the value of sf6 gauges changes accordingly, and cannot accurately indicate the state of the equipment.

SF6 Density Relay Structure

The SF6 Density Relay is mainly composed of a Bourdon tube, gear mechanism and pointer, bimetallic strip and other components. The hollow elastic Bourdon tube is connected to the circuit breaker, and its inner space is connected to the SF6 gas in the circuit breaker. The end of the elastic Bourdon tube is connected to the bimetallic strip, which acts as a temperature compensation. The bimetallic strip is connected to the gear mechanism by a hinge.

SF6 Density Relay Temperature Compensation Principle

The SF6 Density Relay is actually a pressure relay with temperature compensation, and its density value is expressed in the corresponding pressure value at 20℃. When the temperature changes, the elastic Bourdon tube and the bimetallic strip of this type of gas density meter change at the same time, so the pointer remains unchanged.

Under the condition of constant volume, any pressure change caused by temperature change can be compensated simultaneously by the corresponding changes of the Bourdon tube and bimetallic strip, ensuring the accuracy of the pressure indication value.

The response of the pressure element to any pressure change caused by non-temperature factors will be converted into the movement of the gas density relay pointer and reflected on the scale plate, and the pressure value exceeding the minimum or maximum pressure allowed by the system can be monitored.

Requirements for Density Relays

The SF6 Density Relay should be installed in the same operating environment temperature as the monitored gas chamber. If the operating environment temperature is different, the compensation temperature of the Bourdon tube and bimetallic strip will be inconsistent, resulting in inaccurate readings.

LANSO believes that technological innovation is the key to maintaining high-quality service. Committed to R&D and innovation, LANSO and its subsidiaries have developed more than 20 patented solutions, from remote SF6 gas monitoring systems to miniature water detectors. The company has also passed Swiss quality certification. LANSO is constantly striving to provide our customers with high-quality standard and cost-effective solutions. Welcome to consult!

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