Ultrasonic level gauges, as the core equipment for non-contact level measurement, are widely used in fields such as chemical engineering, water conservancy, and food processing. Its high precision and reliability depend on a scientific maintenance system. This article will construct a maintenance plan covering the entire lifecycle from three aspects: daily inspections, regular maintenance, and troubleshooting.

1、 Daily inspection: preventive detail management

Appearance and installation environment inspection are the focus of daily inspections. The operator needs to confirm that the equipment casing is not damaged or cracked, and that the fixing bolts are not loose to prevent sensor displacement due to vibration. For equipment installed outdoors, it is necessary to check whether the sunshade or protective shed is intact to avoid temperature fluctuations caused by direct sunlight or short circuits caused by rainwater infiltration. In strong electromagnetic interference environments (such as near substations), it is necessary to confirm that the equipment grounding wire is firmly connected to prevent signal distortion.

The cleaning of sensor surfaces needs to be included in the handover process. Dip a soft cotton cloth in a small amount of alcohol and gently wipe the surface of the transducer to remove dust, oil, or condensation. Avoid using hard brushes or corrosive cleaning agents to prevent scratching the sensor surface or damaging the waterproof coating. In cement plants with high dust levels, it is recommended to clean them daily; In the clean room, it can be extended to once a week.

The preliminary judgment of the operating status is achieved by observing the instrument display. If there are abnormal fluctuations or fixed values in the liquid level value, it may be due to sensor obstruction or signal interference. It is necessary to immediately check whether there are obstacles within the beam angle (such as agitator blades, pipeline supports). If displayed“No signal”or“overrange”It is necessary to investigate the stability of the power supply or equipment malfunction.

2、 Regular maintenance: Systematic maintenance extends equipment lifespan

Electrical connection inspection should be conducted once every quarter. Focus on checking whether the wiring terminals are oxidized and whether the cable sealing plugs are tightened to prevent moisture from entering and causing short circuits. For split type equipment, it is necessary to confirm that the signal line and power line are arranged separately to avoid mutual interference. In explosive hazardous areas, explosion-proof junction boxes should be used and their sealing performance should be regularly tested.

Functional testing and calibration are the core components of regular maintenance. Verify the measurement accuracy of the equipment at low, medium, and high liquid levels through a standard liquid level simulation device (such as a portable calibration water tank). If the error exceeds the allowable range, parameter correction or hardware adjustment is required. The temperature compensation function needs to be tested with emphasis to ensure that the equipment can maintain stability even in extreme temperature difference environments.

The maintenance of auxiliary facilities cannot be ignored. For equipment with insulation and heat tracing devices, it is necessary to check whether the heating tube is aging and whether the temperature controller is sensitive before winter to prevent sensor damage caused by medium freezing. In outdoor environments, it is necessary to regularly clean the accumulated water at the inlet to prevent cables from getting damp.

3、 Troubleshooting: step-by-step diagnosis and rapid repair

The troubleshooting of no liquid level display should follow“From outside to inside”principle. Firstly, check if the power supply is functioning properly and if the fuse is blown; Secondly, confirm that there are no obstacles within the sensor beam angle and that it is not in the equipment blind zone; Finally, check the instrument parameter settings, such as whether the range and units match. If the problem is still not resolved, an oscilloscope should be used to detect the sensor emission/Receive signals and determine if it is a hardware malfunction.

The fluctuation of liquid level values is often caused by interference. It is necessary to investigate whether there are strong electromagnetic sources such as frequency converters and high-power motors nearby, and if necessary, install metal shielding covers for the equipment. In the scene of fermentation tank with more foam, guide tube installation can be used to reduce false echo interference.

Continuous large errors require system calibration. First, check if the installation height of the sensor has changed, and then perform three-point calibration (low, medium, and high liquid levels) using standard weights or liquid level gauges. If the calibration still does not meet the standard, it may be due to sensor aging, and the manufacturer needs to be contacted to replace the core components.

The maintenance of ultrasonic level gauges is a process“Prevention oriented, precise policy implementation”The protracted battle. By establishing a three-level maintenance system consisting of daily inspections, regular maintenance, and troubleshooting, not only can equipment stability be significantly improved, but unplanned downtime risks can also be reduced, providing solid guarantees for enterprise safety production and efficiency improvement.