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Vortex flowmeter common fault analysis introduction

(1) Fault one

Symptom: After the newly installed or overhauled vortex flowmeter is installed on site, the display instrument has no indication.
Analysis of the cause: no flow or flow in the pipeline is small, no vortex is generated in the sensor; sensor sensitivity is too low; there is debris between the probe and the inner wall of the pipe.

(2) Fault 2
Symptom: There is no fluid flow in the pipe, and the display instrument has flow display.
Cause analysis: Poor instrument grounding introduces external interference; sensor sensitivity is too high.

(3) Fault three
Fault phenomenon: The flow shows that the meter is swinging.
Analysis of the cause: The sensitivity adjustment of the vortex flowmeter amplifier is not suitable; the flowmeter is not installed correctly, so that the medium passing through the meter generates vibration.

(4) Fault four
Symptom: The secondary meter indication is low and slow. Analysis of the cause: It may be that the dirt is blocked between the probe and the inner wall, but it is not blocked.

(5) Fault five
Symptom: A meter is used to indicate a certain scale, and no matter how the sensitivity potentiometer is used, it does not work.
Analysis of the cause: It is generally possible that a component inside the watch is damaged.

4 Fault analysis of vortex flowmeter during use
Symptom: Indicates long-term inaccuracy, no indication at all, indicating that a wide range of fluctuations cannot be read, indicating no return to zero, no indication at small flow, and the meter factor cannot be determined.

Cause Analysis:
(1) Problems in selection. After the caliber selection and design selection, due to changes in process conditions, the selection of specifications is too large. In the actual selection, the smallest possible diameter should be selected to improve the measurement accuracy. Improper selection may result in long-term inaccurate indications, indicating that the fluctuations are too large to read.
(2) Installation problems. The length of the straight pipe at the front and rear of the sensor is not enough, which may cause the indication to be inaccurate for a long time.
(3) Problems with secondary instruments. Common secondary instrument problems include short circuit board, range setting, individual bit display, and K-factor setting, and individual position display is bad, making it impossible to determine the range setting and other parameter settings, resulting in inaccurate meter indication. .
(4) Loop line wiring problem. The connector is not connected, causing the circuit to be interrupted, so that the meter always has no indication.
(5) The connection problem between the secondary instrument and the subsequent instrument. The problem of the subsequent instrument, or the subsequent instrument maintenance, causes the current signal output by the secondary instrument to open, causing the secondary instrument to always have no indication.
(6) Problems with the use environment. Sensors installed in the well, due to high humidity and wet circuit boards, may also cause vortex flowmeter indications to be inaccurate or always indicating no faults. The method of treatment is to regularly clean the vortex flowmeter probe, check the grounding and shielding conditions, and regularly dry or do moisture-proof treatment.

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