Installation of Intelligent Electromagnetic Flow Meter

Intelligent electromagnetic flow meters work based on the principle of electromagnetic induction, so they should be installed away from devices that are prone to electromagnetic interference such as frequency converters, transformers, and motors. The installation location should avoid direct sunlight. The conductivity of the measured fluid should be basically uniform. Attention should also be paid to the following aspects:

1. Upstream and downstream straight pipe sections
In order to achieve the same accuracy as real flow verification for flow meters used on site, it is necessary to meet the specified flow conditions. When the intelligent electromagnetic flowmeter works, it requires uniform flow of upstream fluid, and the disturbance of downstream piping components will not affect the measurement value upstream, that is, a certain length of upstream and downstream straight pipe section is required. Generally, it is required that the length of the straight pipe section of various valves, bends, and reducers upstream of the intelligent electromagnetic flowmeter must be 5-10D or more (D is the inner diameter of the flowmeter), and the length of the downstream straight pipe section should be 2-3D or more.

2. The liquid should be filled in the pipeline
Intelligent electromagnetic flow meters can be installed horizontally, vertically, or at any angle from the horizontal, but the pipeline structure must ensure that the measuring tube is always filled with liquid, otherwise errors will occur. When it is necessary to install the flowmeter on a vertical pipeline from top to bottom, it should be installed at the lower part of the pipeline, and a throttle valve should be installed downstream of the flowmeter to generate a back pressure.

3. No bubbles in the liquid
The pipeline design should ensure that no bubbles will separate from the liquid. Because the valve action will cause pressure changes in the pipeline, resulting in bubbles, the flowmeter should be installed upstream of the valve.

4. The electrode is parallel to the ground
When the intelligent electromagnetic flowmeter is installed horizontally or at an angle to the ground, the electrode connection is parallel to the ground. If the electrode connection is perpendicular to the ground, bubbles are prone to accumulate near the previous electrode to block liquid contact, while the lower electrode is easily covered by mud.
5. The conductivity of the liquid should be stable
Do not install the intelligent electromagnetic flowmeter in areas with extremely uneven fluid conductivity. Especially in the case of chemical injection upstream of the instrument, it is highly likely to cause uneven conductivity, which can have a serious impact on the instrument indication. In this case, chemical substances should be injected downstream of the instrument. If injection is required upstream, the injection point should be kept at a certain distance from the flow meter to ensure even mixing of the liquid.

6. Grounding
Due to the small induced signal voltage of the intelligent electromagnetic flowmeter, it is easily affected by noise, so the flowmeter must be well grounded. Intelligent electromagnetic flow meters are equipped with grounding rings, which are used to establish liquid grounding through contact with the liquid and protect the inner lining. Only in this way can the reference potential of the sensor and the converter/amplifier be ensured to be the same as the measured liquid potential and ground potential, reducing the impact of noise on the measurement results. It must be emphasized that the intelligent electromagnetic flowmeter must be grounded separately. Because if it is grounded together with other instruments or electrical devices, the leakage current in the grounding wire will cause series mode interference to the measurement signal, and in severe cases, the flow meter will not work. In addition, the grounding point should be kept away from large electrical appliances to avoid ground current from entering the flowmeter and causing interference sources. In addition, during the installation process, it should be noted that the electrodes and rubber lining inside the flowmeter should not be damaged during welding (the electrodes are usually two white metal dots). When installing the flowmeter, rubber gaskets should be added between the flanges to prevent water leakage. Outdoor wiring should be avoided on rainy days.