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During on-site maintenance of metal float flowmeters, it is common to observe that the flow indication remains unchanged, stuck at a certain value. A quick way to determine this is to change the relative vertical position between the local remote display unit and the rotor unit, thereby simulating the condition of a floating ball in dynamic flow situations. At this time, the metal float remains fixed. By utilizing the magnetic principle of the float, the moving magnet inside the display is coupled with the float; if the float gets stuck and does not move, moving the display part allows the pointer to change as usual, which proves that the display part is functioning properly. If the pointer cannot change, there is a fault with the remote display and signal power supply. The causes of the failure are as follows: 1. Stuck pointer (1) Damage to the glass panel of the metal float flow meter leads to compression that causes the pointer to get stuck. The solution is to disassemble the display panel and replace the glass panel ； (2) Vibration: During maintenance of other equipment or instruments, impact on the instrument pointers can cause them to deform or become loose, preventing them from reflecting the actual flow rate. The solution is to replace it with a display meter of the same model for installation and adjustment. 2. Pointer jitter: (1) The pointer of a metal float flow meter experiences slight fluctuations due to variations in the pipeline and the medium. (2) Slight fluctuations in the pipelines and media occur due to unstable operating pressure ； For the above faults, it is possible to contact the control room to determine the cause of the issue, adjust the process parameters to stabilize pressure and temperature as well as flow rates, increase the damping of the metal float flow meter, and improve the process environment to ensure stability of the flow meter. 3. Signal power supply failure (1) Damage to the signal amplification and conversion components ； (2) Loose screws causing transmission faults in the circuit ； (3) Fault in the wiring terminals of the DCS control station ； (4) Control station I/O module failure. The method for troubleshooting is to use the \"division method\" to measure the voltage DC (1-5) V at the rear terminals of the control station panel in the control room, in order to determine whether the fault lies on the field side or in the control room. The most common cause of faults is loose terminal screws; such issues can be resolved by tightening the screws. If the fault cannot be resolved, the DCS measurement module can be checked by referring to the terminal wire numbers; look at the fault indicator lights on the module to see if there is any fault. The \"replacement method\" can also be used by swapping in a measurement module of the same model to determine whether normal operation is achieved.