What is the technical principle of interpretation of the electromagnetic flowmeter?

The electromagnetic flowmeter is specially designed with Chinese LCD display with backlight and wide temperature. It has complete and practical functions, intuitive display and convenient operation, which can reduce the inconvenience caused by the English menu of other electromagnetic flowmeters.

In addition, we design a 4-6 multi-electrode structure, which further guarantees the accuracy of the measurement and does not require a grounding ring at any time, thus reducing the volume of the instrument and the problem of installation and maintenance.

Technical principle

1. Working principle. The working principle of the electromagnetic flowmeter is based on Faraday\'s law of electromagnetic induction.

In the electromagnetic flowmeter, the conductive medium in the measuring tube is equivalent to the conductive metal rod in the Faraday test, and the two electromagnetic coilsticks at the upper and lower ends generate a constant magnetic field.

WhWhen a conductive medium flows, an induced voltage is generated. Two electrodes inside the pipe measure the induced voltage generated.

The measurement tube is electromagnetically insulated from the fluid and from the measurement electrodes by a non-conductive coating (rubber, Teflon, etc.).

2. Principle of measurement. According to Faraday\'s law of electromagnetic induction, when a conductor moves through a magnetic field and cuts the magnetic line of force, an induced electric potential e is generated at both ends of the conductor, and its direction is determined by the rule of the right hand, and its amplitude is the same as the magnetic induction intensity B of the magnetic field. The conductor is in the magnetic field The length L of the conductor is directly proportional to the speed of movement u of the conductor. If B, L and u are peperpendicular to each other, then: e=Blu(3-35).

Similar to this. In a uniform magnetic field with a magnetic induction strength of B, a non-magnetic pipe with an inner diameter of D is placed perpendicular to the direction of the magnetic field. When the conductive fluid flows through the pipeline at a rate u When;

The conductive fluid will cross the magnetic field lines. If a pair of electrodes are installed at both ends of the diameter of the pipe section perpendicular to the magnetic field, it can be proved that as long as the flow velocity distribution in the pipe is axisymmetric, the two induced electromotive force is also generated between the electrodes: e=BD (3-36). In the formula, this is the average flow velocity over the pipe section. From this, the pipe volume flow can be obtained as follows: qv=(3-37).

It follows from the above formula thate the volume flow qv is linearly related to the induced electromotive force e and the inner diameter D of the measuring tube, and is inversely proportional to the magnetic force induction strength B of the magnetic field, and has nothing to do with d other physical parameters. Principle of measurement of the flowmeter. Features

Measurement accuracy is unaffected by changes in fluid density, viscosity, temperature, pressure and conductivity. The voltage signal induced by the sensor has a linear relationship with the average flow, so the measurement accuracy is high.

There are no obstructing parts in the metering line, so there is no additional pressure loss; there are no moving parts in the measuring line, so the sensor has a very long service life. Since the induced voltage signal is formed in the whole space filled with magnetic field, it isthe average value on the pipe surface, so the straight pipe section required by the sensor is relatively short, and the length is 5 times the pipe diameter.

The sensor part only has the liner and the electricityThe electrode is in contact with the measured liquid, as long as the materials of the electrode and the liner are selected so reasonable, it can be corrosion and wear resistant.

The LDE converter adopts international single-chip microcomputer (MCU) and surface mount (SMT) technology, with reliable performance, high precision, low power consumption. energy, a stable zero point and convenient parameter adjustment. Click the Chinese to display the LCD screen, displaying the cumulative flow, instantaneous flow, flow velocity, flow percentage, etc.

Bidirectional measuring system, can measure forward flow and reverse flow. The trialSpecial production processes and high quality materials are used to ensure that the product performance remains stable for a long time.

Tag: electromagnetic flowmeter