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How to make the electromagnetic flowmeter function properly for its maximum function

The electromagnetic flowmeter is a meter made by the Faraday electromagnetic induction principle for detecting the flow rate of a conductive liquid (the volume of a liquid passing through a cross section per unit time) and the flow rate.

1. The electromagnetic flowmeter transmitter should be installed in a dry and ventilated place indoors. Avoid installation in places where the ambient temperature is too high, and should not be subjected to strong vibrations. Try to avoid equipment with strong magnetic fields. Such as large motors, transformers, etc. Avoid installation in corrosive gases. The installation location should be easy to access, which is the environmental condition to ensure the normal operation of the transmitter.

2. The electromagnetic flow transmitter should be equipped with valves and bypass at both ends.

3. In order to ensure that the measuring tube of the electromagnetic flow transmitter is filled with the measured medium, the stacker is preferably installed vertically, and the flow direction is from bottom to top. Especially for liquid-solid two-phase flow, it must be installed vertically. If the site is only allowed to be installed horizontally, it must be ensured that the two electrodes are at the same level.

4. In order to avoid interference signals, the signal between the transmitter and the converter must be transmitted with shielded wires. It is not allowed to place the signal cable and power cable in parallel in the same cable. The signal cable length should generally not exceed 30m.

5. The millivolt AC potential measured by the electrodes of the electromagnetic flow transmitter is based on the liquid potential in the transmitter. In order to stabilize the liquid potential and keep the transmitter and fluid at the same potential to ensure stable measurement, the transmitter housing and the metal tube should have a good grounding converter housing and should be grounded. The grounding resistance should not be greater than 10 and cannot be shared with the grounding wire of other electrical equipment. If the transmitter housing is not guaranteed to be in good contact with the metal tubing, connect them with metal wires and ground them reliably.

6. In order to avoid the influence of the flow rate differential measurement, the flow regulating valve should be placed downstream of the transmitter. For small-caliber transmitters, since the distance from the center of the electrode to the inlet end of the flowmeter is equivalent to several times the length of the diameter D, the upstream straight pipe can be omitted. However, for a flowmeter with a large diameter, generally there should be a straight pipe section of 5D or more in the upstream, and the straight pipe section is generally not required in the downstream.

7. The converter installation site should avoid strong magnetic field and vibration of AC and DC. The ambient temperature is -20 to 50 ° C, does not contain corrosive gases, and the relative humidity is not more than 80%.

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