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The reason why the electromagnetic flowmeter fluctuates greatly

The electromagnetic flowmeter fluctuates greatly. There are many kinds of situations that can be called large fluctuations. For example, in the case of no flow, the electromagnetic flowmeter fluctuates greatly, so it needs to be checked: 1. Is it cleaned or flushed after parking; 2. Inspection Is there any interference factors such as motor, frequency conversion, etc. in the vicinity; 3. Check the line for any problems; 4. Check the grounding ring, it may be grounded loose; 4. See if the air traffic controller alarm is set;
If the liquid in the pipe measured by the electromagnetic flowmeter contains a large amount of air bubbles or the liquid in the pipe is not full, the electromagnetic flowmeter will fluctuate greatly, that is, the display value is unstable.
Or the fluid itself is fluctuating or pulsating, so such a fault is not a large fluctuation of the electromagnetic flowmeter, but merely reflects the fluid condition. Or the electromagnetic flowmeter caused by the mismatch between the electrode material of the electromagnetic flowmeter and the liquid is large.
The indirect cause of the large fluctuation of the electromagnetic flowmeter should be that the flowmeter works normally during the commissioning due to the good environmental conditions, and it is often easy to neglect the installation conditions. In this case, once the environmental conditions change, a new source of interference occurs during operation, which will interfere with the normal operation of the meter, and the output signal of the flow meter will fluctuate. The above is only a part of the reason why the electromagnetic flowmeter displays the value of the jump. The possible reasons are as follows: 1. The installation position is incorrect, the tube is not full, or the gas is trapped in the pipe system, or the air bubbles are sucked.
2. A regular pulsating flow generated by a reciprocating pump or the like in the piping system.
3. The liquid contains gas or bubbles.
4. There is a strong magnetic field such as a motor around, and there is stray current on the pipeline.
5. The electrode of the electromagnetic flowmeter is contaminated, or the electrode suitable for the liquid to be tested is not properly selected.
6. The grounding electrode of the electromagnetic flowmeter is not installed in place or interfered by the magnetic field.

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