Vortex flow meter trouble shoot

  Fault classification and treatment method of vortex flowmeter 

Vortex flow meter if commit any faulty, we need deal with it first and find the solutions.

I.  Fault classification

  The types of failures can be divided into two categories: system failures and instrument failures. After a failure occurs, the system failure should be checked first, and if the problem cannot be found, then check whether it is an instrument failure.

  System failures include: incorrect installation and wiring, mismatched caliber, inconsistent flow range, vibration, electromagnetic interference, power supply problems, improper sensitivity adjustment, etc.;

  Instrument failures include: detection probe failure, detection amplifier failure, internal short-circuit, meter body leakage, etc.

II.  Common system failures and treatment

  2.1 There is fluid flowing in the pipeline after power on, but no signal output.

   Check whether the wiring of the meter is correct and whether there is any disconnection.

   Check whether the installation direction of the meter is correct.

   Check whether the flow rate is lower than the normal flow rate range.

  2.2 There is no fluid flow in the power-on pipeline, but there is a signal output.

   Check the grounding of the meter, whether it is a bad grounding that introduces interference.

   Check whether the pipeline has strong mechanical vibration.

   Check whether there is strong electromagnetic interference in the environment, such as high-power electrical appliances or inverters and other strong electrical equipment.

   Check whether the sensitivity is too high, adjust the two potentiometers counterclockwise until there is no output.

  2.3 The flow of fluid in the pipeline is stable and meets the flow requirements, but the output changes too much and is unstable.

   Poor grounding may cause interference.

   It may be that the pipe vibration is too strong to introduce interference.

   It may be that the sensitivity is too low and there is a leakage trigger phenomenon, just increase the sensitivity.

   2.4 The displayed flow does not match the actual flow, and the error is large.

   It may be that the instrument parameter settings are incorrect.

   It may be that the measurement error of the temperature and pressure instrument is too large.

   It may be that the flow rate is lower or higher than the normal flow rate range.

   It may be that the installation does not meet the requirements, such as inconsistent installation, obstacles in the pipeline, and insufficient straight pipe sections.

III. Inspection of instrument failure

  3.1 Simple judgment for detecting amplifier failure

   In the absence of special equipment, use the display instrument to observe the signal, and use the hand to detect the induced signal at the probe lead input end of the detection amplifier.

   can roughly judge whether it is a detection amplifier failure. If there is a signal, it means that the detection amplifier is basically normal, otherwise, the detection amplifier may be faulty.

  3.2 Simple judgment of detection probe failure 

If the instrument has no signal reflection but the detection amplifier has signal reflection, it can be considered that the detection probe may be faulty. To check the quality of the detection probe, use a multimeter to measure the insulation resistance of the two signal wires. When the temperature is lower than 200 degrees, the insulation resistance should be greater than 2MΩ; when the temperature is higher than 200 degrees, the insulation resistance should be greater than 10MΩ. If the insulation resistance meets the requirements, the detection probe is basically normal, otherwise there may be a malfunction.


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