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I. Fault type: Sudden jumps in the level reading displayed by the radar level gauge under the operating conditions of the gas holder. II. Instrument type: Radar level gauge. III. Manufacturer’s model: Xi’an Dinghua Electronics Co., Ltd. DHE-RD-5100. IV. Introduction to operating conditions: Propylene gas tank, range of 17 meters. V. Fault symptom: Sudden jumps in the instrument readings. As shown in the trend chart, the red line often experiences sudden jumps. VI. Safety measures before handling: Since the propylene gas tank is a hazardous area, when there are sudden fluctuations in the instruments, it is necessary to first determine whether it is safe to enter the site to inspect the instruments. A work order must be issued before entering to ensure the safety of the personnel. VII. Analysis of fault causes and reasoning approach: During the initial installation of the radar level gauge, display fluctuations often occur during normal operational conditions. After communicating with the manufacturer’s technical staff, it was learned that there are several possible reasons for sudden fluctuations in radar level gauges: 1. An inappropriate installation location that results in false echoes ； 2. Severe fluctuations in the material surface result in poor echo signals ； 3. Deposits on the sensor surface lead to poor echo signals, and so on. Based on the actual installation conditions on site, the liquid level of the gas holder is at the external floating roof level; the surface of this external floating roof is smooth and flat, and there are no obstacles directly below its installation location, so installation-related issues can be ruled out ； The instrument is suspended and not in contact with any medium, so there is no issue of attachments sticking to it ； When gas cylinders are fed, the external floating roof experiences severe vibrations; when these vibrations are too intense, they can cause signal loss, resulting in poor echo signals and ultimately leading to sudden fluctuations in the instrument readings. After communicating with the manufacturer, an instrument with backscatter tracking functionality was replaced to resolve this issue. VIII. Effective methods for dealing with faults: When gas tanks are being fed, the external floating roof experiences severe vibrations, and when these vibrations are excessive, signal loss can easily occur. It can be determined from this that the instrument’s glitch is caused by poor reception of the echo signal. The solution to this problem is to use a radar level gauge with echo tracking functionality. And pay attention during installation: 1. Try to install the radar above the flat area of the floating roof to avoid false reflections ； 2. The level gauge should not be installed at the center of an arched tank, as this can cause false readings due to enhanced reflections; nor should it be installed too close to the tank walls. The optimal installation location is at 1/2 of the container’s radius. IX. Fault prevention measures and improvements: When selecting a radar level gauge, special attention should be paid to the condition of the medium being measured. In situations where the liquid level fluctuates significantly, it is advisable to use a radar level gauge equipped with an echo tracking function. Of course, radar level gauges with an echo tracking function also have the drawback of increased blind spots, and this function is available only on contactless radar level gauges, not on contact-type ones.