Application of Ultrasonic Level Transmitter in Fire Protection Water Tank

Buildings and properties that have an inadequate water supply for fire flow may require a fire protection water tank. Water tanks for fire protection are used for a variety of applications including to supply fire sprinkler systems, a source of water for firefighting, to create a fire perimeter, at fire departments to fill up trucks, etc. Due to increased regulations and insurance requirements, water tanks for fire protection are increasing in demand. Having a water storage tank ready with the appropriate fire department connections and or ready to supply a fire sprinkler system ensures adequate response in case of an emergency, even in remote areas.

Water supplies for fire protection need the appropriate capacity to reach adequate fire flow, quality of water and pressure needed for the application. According to the fire control regulations, a Xinjiang petrochemical enterprise needs to monitor real-time water level of fire protection water tanks in a control room. Because the water tank of fire protection is located at a high position on the roof, the on-site management staff needs to observe the water level and then go back to the control room to stop the water supply, which requires having full-time staff on duty daily. Based on the above situation, the client urgently needs an instrument which can be used for real-time measurement of the water level rather than manual operation.

However, due to the fire protection water tank is located on outdoor roof and with 15 meters high, and the weather in Xinjiang is hot and dry in summer and extremely cold in winter, so some ultrasonic level transmitters without temperature compensation are easy to be affected by the drastic change of temperature, which leads to the change of sound velocity, thus making false measurement.

In addition, the detection equipment is particularly vulnerable to lightning strike, plus a large central air conditioning system is installed close by the fire protection water tank, which has strong interference. Therefore, the ultrasonic level transmitter must be also featured with the ability of anti-lightning and anti-interference.

According to the requirements and the characteristics of field conditions, Jiwei engineers recommend the Uson-11 Ultrasonic Level Transmitter with a measuring range of 15m. By comprehensive comparison, the client finally adopted the Uson-11 Ultrasonic Level Transmitter.

Ultrasonic Level Transmitter is specifically designed for continuous non-contact liquid level measurement. The transducer (probe) sends out high frequency ultrasonic pulses. When a pulse hits the surface of a measured liquid, it is partially reflected. The reflected wave is received by the transducer and converted into an electronic signal. The distance from the transducer to the liquid surface is calculated according to the time difference between the pulse transmission and reception and velocity of sound wave.

In the Uson series of Ultrasonic Level Transmitters, microprocessor program control technology and intelligent signal processing technology are employed to provide highly efficient and accurate measurements. In comparison with other similar products in the market, Uson series of products has the following advantages:

●　With three selectable measurement ranges, including 5 meters, 10 meters and 15 meters.

●　Certified for high level explosion protection: EX d IIC T6 Gb.

●　With temperature compensation function, it offers high accuracy and strong adaptability.

●　With RS-485 communication interface.

●　Special echo signal processing algorithm is used, which can effectively avoid false echo signals.

●　With IP66/IP67 ingress protection rating.

●　Probe made of corrosion-resistant PVDF, suitable for corrosive liquids or applications under corrosive environment.

●　High cost-effective ratio, low maintenance cost.

●　EMC design of the product complies with IEC61000-4 (GB/T 17626.2) standard in EFT (LT: A), ESD (LT: A) and surge.

EMC design of the products complies with IEC61000-4 (GB/T 17626.2) standard to ensure its stable and reliable performance under severe noise and strong interference working environment. That is to say, the Uson-11 Ultrasonic Level Transmitter has the ability to resist strong electromagnetic interference and lightning. For more accurate measurement, Jiwei engineer suggests the client install a protective shelter for the outdoor instrument to prevent direct influence of temperature change caused by the sun and rain on sound velocity.

Since the Jiwei Uson-11 Ultrasonic Level Transmitter was put into use, it has been running well and solves the problem of water level measurement of fire protection water tanks. Its characteristics of high measurement accuracy, strong adaptability, convenient installation and low maintenance cost are favored by the client.