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Vortex flow meters are developed based on the Karman vortex street principle and are primarily used for measuring the flow rate of fluids in industrial pipelines. They feature low pressure loss, a wide measurement range, and high accuracy; when measuring volumetric flow rates under operating conditions, they are hardly affected by parameters such as fluid density, pressure, temperature, and viscosity. There are no moving mechanical parts, thus it offers high reliability and requires minimal maintenance. It is a relatively advanced and ideal measuring instrument, as its instrument parameters remain stable over the long term. Vortex flowmeters are often referred to as maintenance-free instruments, capable of operating stably and reliably over a long period of time. However, in practical applications there are also some common issues, most of which stem from improper installation and signal interference. The common fault symptoms and their solutions are as follows: (1) Symptom: When there is no flow in the pipeline, the flow display does not show 0. Solution: 1. Check whether the grounding is proper. 2. Check whether the gain is too high. 3. Check whether the pipeline vibration is severe; if necessary, support the pipeline vertically near the flow meter, perpendicular to both the pipeline axis and the vortex generator axis. (II) Phenomenon: There is flow in the pipeline, but it is displayed as 0. Solution: 1. First, check whether the traffic value is below the lower limit or near it. 2. Check whether the connections of the flow sensor/temperature sensor/pressure sensor are secure. 3. Increase the gain and observe. 4. Check whether the temperature and pressure are displayed normally. Check the flow/temperature/pressure sensor circuits using the sensor detection method. (III) Phenomenon: The traffic display is unstable. Solution: 1. First, confirm whether the traffic itself is unstable, and increase the time constant appropriately. 2. Check whether the flow rate is near the lower limit. 3. Check whether the pipeline vibration is severe; add supports if necessary. (IV) Phenomenon: Incorrect current output. Solution: 1. First, confirm that the range of the secondary meter matches the maximum flow rate; the normality of the current output is also determined based on this. 2. Detection current output circuit (enter the engineer menu). 3. Check whether the load resistance of the current circuit is less than the maximum load resistance value of 600 ohms. (5) Phenomenon: The flow rate displayed changes with the actual flow rate, but it does not match the actual flow rate. Solution: 1. Check whether the instrument serial number and tag number match correctly; be careful not to install instruments with different serial numbers in the wrong positions. 2. Check whether the instrument values match those indicated on the nameplate for the instrument constants. 3. When the measurement methods are mass flow rate and standard volume flow rate, check whether the temperature and pressure of the medium under operating conditions differ significantly from those used during design selection. If there is a large difference, the relevant parameters (operating condition density, standard condition density, maximum flow rate, minimum flow rate, etc.) must be calculated and adjusted according to the actual operating conditions. 4. Check whether the straight sections before and after meet the requirements. 5. Check whether the instruments are properly aligned during installation. 6. Check whether the inner diameter of the pipeline matches that of the instrument. 7. Check the sealing gasket; it must not be inserted into the pipeline. 8. Check whether the inner wall of the pipeline is smooth. 9. Check whether the installation angle and direction are correct, and whether the flow direction of the medium matches the arrow. 10. Check whether there is two-phase flow in the medium being measured; for example, use a moisture separator to remove small water droplets from wet steam, or employ an appropriate filter to remove solid particles from gases. 11. Check whether the flow rate is near the lower limit; a flow rate below this limit makes accurate and stable measurement impossible. 12. Check the sensor to verify that the capacitance and insulation resistance values are within the specified range.