Electromagnetic flowmeter working principle:
The electromagnetic flowmeter is suitable for measuring the volume flow of conductive liquid and slurry in a closed pipe. Its working principle is based on Faraday's law of electromagnetic induction: when a conductor moves in the magnetic field, the conductor in the direction perpendicular to the direction of the magnetic field and the direction of motion The magnitude of the electromotive force is proportional to the size of the conductor's velocity and the magnetic induction intensity of the magnetic field. The electromagnetic flowmeter consists of a transmitter and a converter. The transmitter (also known as the sensor) is based on Faraday's law of electromagnetic induction. The principle is shown in the following figure: The measuring tube is equipped with an excitation coil up and down, and the two electromagnetic coils at both ends of the upper and lower excitation current generate a constant magnetic field. When the measured medium (ie, the conductive medium in the measuring tube) flows perpendicularly to the magnetic field line Induction potential Ex; a pair of electrodes mounted on the measuring tube wall and liquid contact, lead the induced voltage, sent to the converter. In recent years, with the deepening of theoretical technology, people in the design and manufacture, in the measurement of the electrode plane to add two ground electrode, so no need to add a grounding ring can eliminate electrical noise interference.