When using Emerson mass flow meters, attention should be paid to the influence of the environment

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The electromagnetic flowmeters of Emerson’s quality flowmeter series are often used to measure dirty fluids; over time, an accumulation layer can form on the inner walls of the sensor, leading to malfunctions. These failures are often caused by the conductivity of the adhesion layer being too high or too low. If the adhering layer is an insulating layer, the electrode circuit will experience an open circuit, and the instrument will not function properly; if the conductivity of the adhering layer is significantly higher than that of the fluid, the electrode circuit will experience a short circuit, and again the instrument will not function properly. Therefore, the accumulated scale layer inside the measuring tube of the electromagnetic flowmeter should be removed in a timely manner. Furthermore, lightning can easily induce high voltages and surge currents in the instrument circuits, causing damage to the instruments. It is introduced mainly through the power cable, the excitation coil, or the flow signal line between the sensor and the converter, with the majority coming from the power cable in the control room. Sometimes the operating environment is good and the flow meter can function properly, but it’s easy to overlook the installation conditions at such times (for example, poor grounding). Under such circumstances, once the environmental conditions change or new sources of interference arise during operation (such as welding on pipes near the flow meter or the installation of large transformers in the vicinity), it can disrupt the proper functioning of the instrument, resulting in fluctuations in the output signal of the flow meter. Therefore, it is necessary to regularly check the impact of the environment on the flow meter during its use, in order to make better use of Emerson’s quality flow meters.