What are the installation requirements of electromagnetic flowmeter?

Electromagnetic flowmeter is a flow meter, mainly used to measure the volume flow of conductive liquids and slurries in closed pipes. Electromagnetic flowmeters are widely used in industries such as petroleum, chemical industry, metallurgy, textile, food, pharmaceutical, papermaking, as well as environmental protection, municipal management, water conservancy construction, etc. Let's take a look at the installation requirements of electromagnetic flowmeters, hoping to help everyone.

Installation requirements of electromagnetic flowmeter

1: The electromagnetic flow transmitter should be installed in a dry and ventilated place indoors. Avoid installing it in places where the ambient temperature is too high. It should not be subjected to strong vibrations and try to avoid equipment with strong magnetic fields, such as large motors, transformers, etc. Avoid installing it in places with corrosive gases. The installation location should be convenient for maintenance. This is the environmental condition to ensure the normal operation of the transmitter.

2: In order to ensure that the measuring tube of the electromagnetic flow transmitter is filled with the measured medium, the transmitter is best installed 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 ensured that the two electrodes are on the same horizontal plane.

3: Valves and bypasses should be installed at both ends of the electromagnetic flow transmitter.

4: 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 the fluid at the same potential to ensure stable measurement, the transmitter housing and both ends of the metal pipe should be well grounded, and the converter housing should also be grounded. The grounding resistance cannot be greater than 10, and it cannot be shared with the grounding wire of other electrical equipment. If it is not possible to ensure that the transmitter housing is in good contact with the metal pipe, use a metal wire to connect them and then reliably ground them.

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

6: The installation location of the converter should avoid strong AC and DC magnetic fields and vibrations, the ambient temperature should be -20 to 50°C, it should not contain corrosive gases, and the relative humidity should not exceed 80%.

7: In order to avoid the influence of velocity distribution on measurement, the flow control valve should be set at the downstream of the transmitter. For small-diameter transmitters, since the distance from the electrode center to the inlet of the flowmeter is equivalent to several times the length of the diameter D, there is no requirement for the upstream straight pipe. However, for flowmeters with larger diameters, there should generally be a straight pipe section of more than 5D upstream, and there is generally no requirement for a straight pipe section downstream.