Installation method of intelligent electromagnetic flowmeter

  • 2022-07-21 18:19:33
  • 0time

The intelligent electromagnetic flowmeter is an electromagnetic induction flowmeter, which consists of sensors and intelligent signal converters. It can measure the volume flow of various conductive liquids, the measured media include strong corrosive liquids such as acid, alkali, salt, raw water, cooling water and other conductive liquids and solid-liquid two-phase liquids.

In order to ensure the measurement accuracy of the electromagnetic flowmeter, please observe the following points during installation:

1: The transmitter should be installed in a ventilated and dry place. Avoid installing it in a place where the ambient temperature is too high, and try to avoid equipment with strong magnetic fields, such as large motors, transformers, etc. Avoid installing it in places with corrosive gases. Installation location To facilitate maintenance.

2: In order to ensure that the measuring tube of the transmitter is filled with the measured medium, it is best to install the variable transformer vertically with the flow direction from bottom to top. Especially for liquid-solid two-phase flow, it must be installed vertically. If only horizontal installation is allowed on site, it must be installed vertically. Make sure the two electrodes are at the same level

3: In order to avoid the influence of the relative measurement of the flow rate, the flow control valve should be set downstream of the transmitter. For small-diameter transmitters, the distance from the center of the electrode to the inlet end of the flowmeter is equivalent to several times the diameter D. Therefore, there is no requirement for the upstream straight pipe. However, for a flowmeter with a larger diameter, there should generally be a straight pipe section above 5D in the upstream, and generally no straight pipe section is required in the downstream.

4: Valves and bypasses should be installed at both ends of the transmitter.

5: The AC potential of several millivolts measured by the electrode 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 the fluid at the same potential to ensure stability The transmitter casing and both ends of the metal pipe should be well grounded, and the converter casing should also be grounded. The grounding resistance should not be greater than 10, and it should not be shared with the grounding wire of other electrical equipment. If the transmitter housing cannot be guaranteed to be in good contact with the metal pipes, use metal wires to connect them. Then ground them reliably.

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

7: In order to avoid interfering signals, the signal between the transmitter and the converter must be transmitted with shielded wires. It is not allowed to put the signal cable and the power cable in parallel in the same cable steel pipe. The length of the signal cable should not exceed 30m in general