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This post was last edited by yunrun on 2020-6-10 at 12:38. Users should read the \"User Manual for Ultrasonic Level Gauges\" carefully before putting them into use, and the installation of these devices must comply with the requirements outlined in these installation specifications. 1. Installation requirements for ultrasonic level gauges: When the transducer of an ultrasonic level gauge emits ultrasonic pulses, it has a certain emission angle. There must be no obstacles in the area radiated by the emitted ultrasonic beam, from the lower edge of the transducer to the surface of the medium being tested; therefore, during installation, care should be taken to avoid facilities inside the tank, such as ladders, heating equipment, and limit switch brackets. In this case, “pseudo-echolocation*” must be performed during installation. Also, note that the ultrasonic beam must not intersect with the feed stream. When installing an integrated ultrasonic level gauge, it is also important to note that the maximum material level must not enter the measurement blind zone ； The integrated ultrasonic level gauge must maintain a certain distance from the tank wall ； When installing an integrated ultrasonic level gauge, the transducer should be kept perpendicular to the liquid surface as much as possible ； Integrated ultrasonic level gauges installed in hazardous areas must comply with the installation regulations for explosion-proof hazardous areas. The intrinsically safe integrated ultrasonic level gauge is installed in areas where explosion protection is required, and the ultrasonic level gauge must be grounded. 2. Basic requirements for the installation of ultrasonic level gauges: When the transducer of an ultrasonic level gauge emits ultrasonic pulses, it has a certain emission angle. There must be no obstacles in the area radiated by the emitted ultrasonic beam, from the lower edge of the transducer to the surface of the medium being tested; therefore, during installation, care should be taken to avoid facilities inside the tank, such as ladders, heating equipment, and limit switch brackets. In this case, “pseudo-echolocation*” must be performed during installation. Also, note that the ultrasonic beam must not intersect with the feed stream. When installing an integrated ultrasonic level gauge, it is also important to note that the maximum material level must not enter the measurement blind zone ； The integrated ultrasonic level gauge must maintain a certain distance from the tank wall ； When installing an integrated ultrasonic level gauge, the transducer should be kept perpendicular to the liquid surface as much as possible ； Integrated ultrasonic level gauges installed in hazardous areas must comply with the installation regulations for explosion-proof hazardous areas. The intrinsically safe integrated ultrasonic level gauge is installed in areas where explosion protection is required, and the ultrasonic level gauge must be grounded. http://yunrun.com.cn/upload/201603/30/201603302258108378.jpg The reference level for measurement is the lower edge of the ultrasonic level gauge transducer. Note: ① Range of the blind zone ； ②Range setting ； ③High-level adjustment ； ④Low-level adjustment 3. Installation location of ultrasonic level gauge: http://yunrun.com.cn/upload/201603/30/201603302258465386.gif When installing, it is important to ensure that there is at least a 200mm distance between the integrated ultrasonic level gauge and the tank wall. ①For reference level ②, at the center of the container or along its axis of symmetry, an integrated ultrasonic level gauge should be installed in the center of the top of a conical tank. In the case of a conical container with a flat top, the optimal installation location for the gauge is the center of the tank’s top, as this ensures that the bottom of the container can be measured accurately. http://yunrun.com.cn/upload/201603/30/201603302259567712.jpg The image shows the correct and incorrect installation positions for ultrasonic level gauges. http://yunrun.com.cn/upload/201603/30/201603302300187087.jpg ① Incorrect: The transducer should be perpendicular to the surface of the medium being measured. ②Error: Installing an integrated ultrasonic level gauge on a vaulted or circular tank roof can result in multiple reflected echoes, which should be avoided as much as possible during installation. ③It is the correct method for installing an ultrasonic level gauge: http://yunrun.com.cn/upload/201603/30/201603302301017608.jpg ① Incorrect: Do not install the integrated ultrasonic level gauge above the feed stream, in order to ensure that the surface of the medium is being measured and not the feed stream itself. ②When installing the meter box correctly, sun protection and rain protection measures should be taken. 4. Moisture protection for integrated ultrasonic level gauges: http://yunrun.com.cn/upload/201603/30/201603302302120809.gif For integrated ultrasonic level gauges installed in outdoor areas, humid indoor environments, or on the tops of refrigeration or heating tanks, it is necessary to tighten the cable seals in order to prevent moisture from entering. Additionally, the cable should be bent at the point where it enters the gauge (as shown in the image on the left). 5. Container connections for integrated ultrasonic level gauges: http://yunrun.com.cn/upload/201603/30/201603302302281483.gif The length of the container connection must ensure that the probe extends at least 10 mm beyond the end of the connection. http://yunrun.com.cn/upload/201603/30/201603302303004848.gif ① When the medium has good reflectivity and the diameter of the container connection is large, the length of the connection can be slightly longer than the values recommended in the table on the right side of Figure 1 for different diameter connections. At this point, the end of the connector must be smooth and free of burrs, with as much rounding as possible. Additionally, “false echo imaging*” must be performed. ②When the reflectivity of the medium is poor and the maximum liquid level might reach a blind area, it is necessary to raise the installation position of the connector of the integrated ultrasonic level gauge. In such cases, a trumpet-shaped wave guide can be used to increase the directionality of the signal and reduce the impact of the connector on the measurement (Figure 2). 6. The effect of stirring on ultrasonic level gauges: http://yunrun.com.cn/upload/201603/30/201603302303294145.gif When there is stirring in the tank, the integrated ultrasonic level gauge should be placed away from the stirrer. After the gauge is installed, it is necessary to conduct a “false echo test” while the stirring is in operation, in order to eliminate the influence of false echoes generated by the stirrer blades. If foam is generated or waves are created due to stirring, the waveguide installation method should be used. 7. The effect of foam on ultrasonic level gauges: During processes such as feeding, stirring, or other operations within the container, foam can form on the surface of certain media, thereby attenuating the signals from ultrasonic level gauges. If foam causes errors, the sensor should be installed inside a waveguide or a waveguide radar level gauge should be used. Guided wave radar level gauges are not affected by foam, making them the best choice for such applications. 8. Effect of air currents on ultrasonic level gauges: If there are strong air currents inside the container, such as when the device is installed outdoors in windy conditions, or if there are air vortices within the container, the sensor should be installed inside a wave guide, or a guided-wave radar level gauge should be used. Recommended reading: Nine typical troubleshooting methods for ultrasonic level gauges http://yunrun.com.cn/tech/3122.html