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I. Regarding jitter: Mild jitter is usually caused by medium fluctuations, and it can be overcome by increasing damping； Moderate vibration is usually caused by the flow conditions of the medium; in the case of gases, it is often due to unstable operating pressure of the medium. Pressure stabilization or flow regulation devices can be used to overcome this issue or increase the damping of the instrument air ； Severe shaking is mainly caused by medium pulsations, unstable air pressure, or discrepancies between the pressure, temperature, and flow rates specified by the user for gas operation and the actual conditions indicated by the instrument, such that these differences are large enough to cause the instrument to exceed its range. II. The pointer stops moving at a certain position; the main reason is that the float is stuck. Generally, this occurs because the valve is opened too quickly when using the gauge, causing the float to rush upward toward the stopper at high speed; this results in the stopper deforming and trapping the float. However, it is also possible that the float gets stuck due to the float guide rod and the stop ring not being aligned. During processing, the gauge can be removed; the deformed stopper should be taken off and reshaped, and it should be checked to see if it is aligned with the guide rod. If not, alignment adjustments can be made. After that, the float should be reinstalled, and the float should be pushed by hand to ensure that it moves up and down smoothly without any obstruction. Additionally, when installing the gauge, it must be installed vertically or horizontally – it cannot be tilted, as this can also cause problems with the gauge and lead to measurement errors. III. Large measurement errors: One reason is that the installation does not meet the requirements. Installation requirements: For vertically installed instruments, they must remain vertical, with an inclination of no more than 2° ； For horizontally installed instruments, they must remain level, with an inclination of no more than 2° ； There must be no ferromagnetic objects within 100 mm of the instrument ； The installation location should be far away from valve diameter changes, pump outlets, and bends in the process pipelines. The requirement of a 5D front section and a 250 mm straight pipe section at the back must be maintained. Secondly, it is due to the large variations in the density of the liquid medium, which is also a cause of significant errors. Since, before calibration, the medium is converted to an equivalent density as specified by the user in order to calibrate it using the flow rate of water under standard conditions, any significant change in the density of the medium can lead to large measurement errors. The solution is to substitute the altered medium density into the formula to calculate an error correction factor, and then multiply the flow rate measured by the flow meter by this factor to obtain the actual flow rate. Thirdly, since gas media are greatly affected by temperature and pressure, it is recommended to use temperature and pressure compensation to obtain the true flow rate. Fourth, due to factors such as long-term use and pipeline vibration, moving parts of the instrument such as the sensing magnet, pointer, counterweight, and rotating magnet become loose, resulting in significant errors. Solution: You can first verify by manually pushing the pointer. First, place the pointer at the RP position and check whether the output is 4 mA and whether the flow display shows 0%. Then verify sequentially according to the scale. If any discrepancy is found, the position of the component can be adjusted. It is generally required that professionals make adjustments; otherwise, the position will be lost and it will be necessary to return to the manufacturer for correction. IV. No current output: First, check whether the wiring is correct ； Next, check whether the liquid crystal displays anything; if it does display but there is no output, it is usually due to a damaged output transistor, and the circuit board needs to be replaced ； Furthermore, the loss of calibration values – resulting from E2PROM failures that cause the loss of instrument calibration data – can also lead to no output current, with the current remaining unchanged. Solution: Data recovery operations can be used; if that doesn’t work, the data in password 2000 can be set first, followed by the data in password 2008, by manually adjusting the pointer to set the values from RP–100%. V. No on-site display: First, check whether the wiring is correct. Next, check whether the power supply is correct. Finally, reinstall the liquid crystal module and check for poor contact.