Application of ELL external-mounted level gauges in hazardous tank areas

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Since the issuance of Document No. 116 by the Safety Supervision Bureau in 2014, it has become urgent to upgrade safety instrument systems and systems related to major hazard sources. Safety instrumentation System, abbreviated as SIS ； Also known as the Safety Interlocking System. It mainly refers to the alarm and interlock sections in factory control systems. It has the functions of ensuring the normal operation of production and providing safety interlocks in case of accidents, and is an essential supporting system for modern chemical enterprises. It is important to choose a gauge with SIL certification. Dinghua Electronics’ external level measurement instruments obtained the SIL3 certification in 2017, successfully assisting thousands of users in carrying out upgrades to their safety instrumentation systems. Why do so many manufacturers choose Dinghua Electronics’ external level gauges? Today, we’ll reveal the secret: https://bbs.hcbbs.com/forum.php?mod=image&aid=2137015&size=300x300&key=dd9bda59808c3c37&nocache=yes&type=fixnone The principle of sonar ranging is the basis for using ELL external level gauges to measure liquid levels. It works by having a level sensor attached to the bottom of the tank emit sound waves of a certain frequency; these waves penetrate the tank wall and travel through the liquid inside the tank, where they are reflected off the liquid surface to form echoes. These echo signals return to the bottom of the tank, pass through the tank wall again, and are then captured by the level sensor. The sensor transmits these returned sonar signals to the main unit, which calculates the liquid level using the formula Distance (D) = Speed (S) × Time (T). Where: Distance (D): The desired liquid level height. Speed (S): The speed at which sound waves propagate through a liquid medium; the speed of sound waves varies depending on the medium. Time (T): The time it takes for sound waves to generate an echo in a liquid. 2.1.2 The “micro-vibration analysis” technique is the guarantee for the stable and reliable operation of ELL external level gauges. It is easy to see from the basic working principle of the ELL external level gauge that it is crucial to accurately calculate the liquid level height in the container in order to obtain an accurate time variable (T). Due to the complex operating conditions of some storage tanks, the ELL external level gauge equipped with \"micro-vibration analysis\" technology can automatically identify the correct level signal and continuously track it to display an accurate level. In addition, its unique learning characteristics enable it to identify and reject interference such as residual shocks on the container walls, multiple echoes, and false echoes. Complex echo recognition algorithms ensure that the liquid level can always be effectively tracked and monitored. https://bbs.hcbbs.com/forum.php?mod=image&aid=2137013&size=300x300&key=c17ed9573cf453b5&nocache=yes&type=fixnone2.1.3 Automatic calibration technology is the guarantee for accurate measurement by ELL external level gauges. When the temperature of the same liquid medium changes significantly, as well as when there are substantial changes in the liquid’s composition and density, this has a significant impact on the speed of sound waves traveling within the liquid, resulting in measurement errors. The accuracy of the instruments can be ensured by installing a calibrator inside the container, and using a calibration probe outside the container wall to measure the standard length of the liquid column inside the calibrator (the standard length being 1 meter). The instrument will automatically use the corrected sound wave propagation speed for calculations. The length of the liquid column inside the calibrator is 1 meter by standard; in this case, the calibrator functions like a ruler. The calibration probe continuously sends the values obtained from this ruler to the CPU, which then uses these values to calculate the exact height of the liquid surface. The height thus determined is an accurate value that is not affected by changes in the temperature or composition of the liquid. The principle of automatic calibration involves identifying a section of known length on the container as a scale, using it to self-calibrate the external level gauge, thereby ensuring high-precision level measurement under any operating conditions. If a calibrator cannot be installed in the container under any circumstances, the exact known diameter of the container can be used as a reference for automatic calibration. 2.2 Advantages of the ELL external-type level gauge: The ELL external-type level gauge employs a \"completely isolated\" measurement method, and its proprietary \"micro-vibration analysis technology\" as well as \"automatic calibration technology\" ensure high measurement accuracy as well as stability and reliability. The ELL external level gauge makes no contact with the liquid inside the container at all; it is installed on the outer bottom and side walls of the container, and uses sensors to capture the sonar echo signals from the liquid within the tank. By analyzing and interpreting these sonar echo signals, and by employing proprietary algorithms, it is possible to calculate the liquid level height inside the container in real time. At the same time, the patented calibration algorithm ensures high measurement accuracy of the instrument over a long period of time. Easy and fast for installation, repair, and maintenance; safe and reliable in use, without the need to empty the tank, use fire, or disrupt normal production ； It uses no valves or flanges, thus avoiding additional leakage points and ensuring high safety. The instruments are explosion-proof and have a high protection level; even when damaged or under maintenance, they pose no risk of leakage, toxicity, or explosion. The ELL external level gauge has no moving parts, does not wear out, and requires very little maintenance. https://bbs.hcbbs.com/forum.php?mod=image&aid=2137014&size=300x300&key=17b9f60349031bbd&nocache=yes&type=fixnone2.3 Features of the ELL external level gauge: 1) Innovative design for reliable performance: The automatically calibrating external level gauge continuously adjusts itself to maintain the highest measurement accuracy at all times. 2) Harsh operating conditions: ultra-high pressure vessels and high-purity media; the ELL series maintains its functionality regardless of temperature and pressure, enabling reliable measurements in challenging situations. Contactless level gauges are ideal for corrosive substances, such as corrosives, strong acids, strong bases, and other chemicals. https://bbs.hcbbs.com/forum.php?mod=image&aid=2137011&size=300x300&key=72fbf9f2208e7dae&nocache=yes&type=fixnone3) For open tanks and atmospheric pressure vessels, external level gauges can provide reliable level measurement. It is not affected by complex surface conditions and can provide stable data. 4) Simplified maintenance: ELL instruments enable online maintenance without affecting production. 5) Simplified installation to save on costs: The communication between the ELL series level gauges and the control room can be achieved using Modbus in most existing cable installations, which means there is no need for expensive cable conduits. Each level gauge can be installed online, without the need to stop production or empty the tank, and no holes need to be made in the container. 6) Environmentally friendly: no holes or flanges required, reducing leakage points. https://bbs.hcbbs.com/forum.php?mod=image&aid=2137010&size=300x300&key=1a5b89b3ab0b783e&nocache=yes&type=fixnone3 The actual performance of the ELL external level gauge: The workload associated with instrument maintenance has decreased, as the ELL external level gauge is simple to maintain and easy to operate, resulting in a **reduction in the amount of maintenance required**.