Reason why the metal float gauge pointer does not change

In the field maintenance and overhaul of the metal float flowmeter, it is often seen that the flow indication is unchanged and fixed at a certain value. The quick determination method is to change the position of the local remote transmission display part and the rotor part up and down to simulate the state of the float dynamic flow. At this point the metal float is fixed, using the magnetic principle of the float, the follower magnetic steel in the display is linked to the float and if the float is stuck, the pointer of the mobile display part can be normally changed to show that the display part is normal. If the pointer can not be changed to find the remote display and signal power failure. The cause of the fault is the following:

1. The pointer is stuck

(1) Metal floater flowmeter glass panel damage Squeeze pointer stuck. The processing method is: open the display table to replace the glass panel;

(2) Vibration, when the other equipment is overhauled or the instrument is overhauled, the instrument pointer will be loosely deformed so that the deformation of the pointer will not reflect the actual flow value. The method is: replace the installation adjustment with the equivalent model display.

2 pointer jitter

(1) The metal float gauge pointer will fluctuate slightly due to line and medium fluctuations.

(2) Pipelines and mediums cause slight fluctuations due to unstable operating pressure;

The above faults can be contacted with the control room to find out the operation reasons, adjust the process parameter stable pressure, temperature flow, increase the damping of the metal float meter, and improve the process environment to stabilize the flow meter.

3. Signal power failure

(1) Failure of the signal amplification conversion component;

(2) loose screw line transmission failure;

(3) DCS control station terminal failure;

(4) The control station I/O module is faulty.

Troubleshooting method is: using the "segmentation method" in the control room to control the station disc terminal voltage measurement DC (1-5) V, analysis and judgment is the scene of fault or control room failure, the highest failure rate is the terminal screw loose, fastening screw failure Can be ruled out. Failure can not be ruled out by looking for the fault of the DCS measurement module according to the terminal line number, looking for the fault indicator of the module to see if there is a fault, or replacing the measurement module of the same model with the “replacement method” to see if the display is normal.