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Analysis of common faults in vortex flowmeters (1) Fault 1. Fault phenomenon: After the newly installed or repaired vortex flow meter is installed on-site, the instrument shows no indication. Cause analysis: There is no flow or only very little flow in the pipeline, and no vortices are generated inside the sensor ； The sensitivity of the sensor is too low ； There is debris stuck between the probe and the inner wall of the pipe. (2) Fault two. Fault symptom: No fluid flow in the pipeline, yet the display instrument shows flow rate. Cause analysis: Poor grounding of the instrument leads to external interference; the sensor has too high sensitivity. (3) Fault three. Fault symptom: The flow display gauge fluctuates. Cause analysis: The amplifier sensitivity is not set properly ； The flow meter was installed incorrectly, causing vibration in the medium passing through it. (4) Fault four. Fault symptom: The secondary meter shows a low reading and responds slowly. Cause analysis: It is possible that debris is blocked between the probe and the inner wall, but not completely blocked. (5) Fault five. Fault symptom: As soon as power is applied, the gauge indicates a certain scale value, and adjusting the sensitivity potentiometer has no effect. Cause analysis: It is generally likely that a component inside the gauge has been damaged. Fault analysis of vortex flowmeters during use. Fault symptoms: inaccurate indication over a long period, no indication at all, large fluctuations in the indication making it impossible to read the value, failure of the indication to return to zero, no indication at low flow rates, and inability to determine the meter coefficient. Cause analysis: (1) Issues with product selection. After the selection of the diameter and design parameters for vortex flowmeters, changes in process conditions can lead to the choice of a specification that is too large. In actual selection, the smallest possible diameter should be chosen to improve measurement accuracy. Improper selection may result in inaccurate readings over time, as well as large fluctuations that make it impossible to obtain readable values. (2) Issues related to installation. Insufficient length of the straight sections in front of and behind the sensor can also lead to inaccurate readings over time. (3) Problems with secondary instruments. Common problems with secondary instruments include short circuits in the circuit boards, faulty display of certain values related to the measurement range, and faulty display of certain values related to the K coefficient. These issues prevent accurate determination of the measurement range and other parameters, resulting in inaccurate readings from the instrument. (4) Circuit wiring issues. The connection was not made properly, resulting in an interruption in the circuit and preventing the instrument from giving any readings. (5) Connection issues between secondary instruments and subsequent instruments. Issues with the subsequent instruments, or maintenance work on those instruments, can cause the current signal output by the secondary instruments to become open-circuited, resulting in the secondary instruments not showing any indication at all. (6) Issues related to the usage environment. Sensors installed in wells may experience inaccurate readings or no readings at all due to high humidity, which causes the circuit boards to become damp. The solution involves regularly cleaning the vortex flowmeter probe, checking the grounding and shielding conditions, and periodically drying it or taking measures to prevent moisture from affecting it.