1. Product overview:

LDE series electromagnetic flowmeter is an inductive instrument that measures the volume flow of conductive medium in the pipe according to Faraday's law of electromagnetic induction. It adopts the embedded technology of single-chip microcomputer to realize digital excitation, and adopts CAN field bus on the electromagnetic flowmeter. The technology has reached the highest level in China. high level. While satisfying on-site display, it can also output 4-20mA current signal for recording, adjustment and control. In addition to measuring the flow of general conductive liquids, the meter can also measure liquid-solid two-phase flow, high-viscosity liquid flow and salts , Volume flow of strong acid and strong alkali liquid.

The integrated electromagnetic uses constant current low-frequency three-valued rectangular wave or dual-frequency rectangular wave excitation, which not only has the advantages of rectangular wave magnetic field, but also overcomes the shortcomings of sine wave magnetic field; it can also eliminate power supply voltage fluctuation, power supply frequency change and excitation coil impedance change The error caused by; and has excellent zero stability and is not affected by fluid noise. So it has the characteristics of high stability and high reliability. The electromagnetic flowmeter is composed of a sensor and a converter, the sensor is installed on the measuring pipe, and the converter can be combined with the sensor, which is called an integrated flowmeter.

The split type electromagnetic adopts the split type design, which is convenient for maintenance and increases the service life of the electromagnetic flowmeter. The wall-mounted flow converter can effectively protect the sensor conversion circuit, which is conducive to anti-corrosion, moisture-proof and waterproof. The wiring of the product is simple and the installation is convenient. The split electromagnetic consists of a sensor and a converter. The sensor is installed on the measuring pipe, and the converter is installed within 30 meters or 100 meters from the sensor. The two are connected by a shielded cable to measure the volume flow of conductive liquids. The main components of the sensor are: measuring tube, electrode, excitation coil, iron core and yoke shell. Mainly used to measure the volume flow of conductive liquids and slurries in closed pipes.

2. Working principle:

According to Faraday's electromagnetic induction principle, LDE series electromagnetic flowmeters install a pair of detection electrodes on the tube wall perpendicular to the axis of the measuring tube and the magnetic field lines. When the conductive liquid moves along the axis of the measuring tube, the conductive liquid cuts the magnetic field lines to generate an induced potential. The induced potential is detected by two detection electrodes, and the value is proportional to the flow rate. Its value is: E=KBVD where:

E - induced potential;

K - coefficient related to magnetic field distribution and axial length;

B - magnetic induction intensity;

V - average flow rate of conductive liquid;

D - electrode spacing; (measuring tube inner diameter)

The sensor takes the induced potential E as a flow signal and transmits it to the converter. After amplification, conversion filtering and a series of digital processing, the instantaneous flow and cumulative flow are displayed by a dot-matrix liquid crystal with backlight. The converter has 4 ~ 20mA output, alarm output and frequency output, and is equipped with RS-485 and other communication interfaces, and supports HART and MODBUS protocols.

3. Application occasions:

LDE series electromagnetic flowmeters are mainly used to measure the volume flow of conductive liquids and slurries in closed pipes. Such as water, sewage, mud, pulp, various acids, alkalis, salt solutions, food slurries, etc., are widely used in petroleum, chemical, metallurgy, textile, food, pharmaceutical, paper and other industries as well as municipal management, water conservancy construction and other fields.

4. Structural form:

1. Sensor:

The sensor is mainly composed of measuring conduit, measuring electrode, excitation coil, iron core, magnetic yoke and shell.

a. Measuring conduit: It is composed of stainless steel conduit, lining and connecting flange, which is the carrier for measuring the on-site working conditions of the liquid to be measured.

b. Measuring electrodes: a pair of electrodes installed on the inner wall of the measuring conduit, perpendicular to the direction of the axial flow, to enable the measuring liquid to generate signals.

c. Excitation coil: The upper and lower excitation coils generate a magnetic field in the measuring catheter.

d. Iron core and yoke: The magnetic field generated by the excitation coil is introduced into the liquid to form a magnetic circuit.

e. Shell: the outer packaging of the instrument.

2. Converter:

It is an intelligent secondary meter. After amplifying the flow signal and processing the single-chip operation, it can display the flow rate and accumulated amount, and can output signals such as pulse and analog current, which are used for the measurement or control of fluid flow.

3. Product assembly form:

It is divided into two forms: one-body type and split-body type.

a. Integrated type: The sensor and the converter are installed together.

b. Split type: The sensor and the converter are installed separately, and the flow measurement system is formed by connecting the cable.

c. In order to meet the measurement requirements of different media, the lining and electrode materials of the sensor can be selected in a variety of ways.

Five, the main features:

1. The instrument has a simple and reliable structure, no moving parts, and long working life;

2. There is no interception and blocking parts, and there is no pressure loss and fluid blockage;

3. No mechanical inertia, fast response, good stability, can be used in automatic detection, adjustment and program control systems;

4. The measurement accuracy is not affected by the type of the measured medium and its temperature, viscosity, density, pressure and other physical parameters;

5. Different combinations of PTFE or rubber lining and electrode materials such as Hc, Hb, 316L, Ti can meet the needs of different media;

6. Various flowmeter models such as pipeline type and insertion type are available;

7. Using EEPROM memory, the storage protection of measurement and operation data is safe and reliable;

8. There are two types of integration and separation;

9. High-definition LCD backlight display.

6. Technical parameters:

1. Instrument accuracy: pipeline type 0.5, 1.0; plug-in type 2.5.

2. Measurement medium: various liquids and liquid-solid two-phase fluids with electrical conductivity greater than 5μS/cm.

3. Velocity range: 0.2～8m/s.

4. Working pressure: 1.6MPa.

5. Ambient temperature: -40℃～+50℃.

6. Medium temperature: PTFE lining≤180℃; rubber material lining≤65℃.

7. Explosion-proof mark: ExmibdⅡBT4.

8. Explosion-proof certificate number: GYB01349.

9. External magnetic interference: ≤400A/m.

10. Shell protection: integrated type: IP65;

Separate type: sensor IP68 (underwater 5 meters, rubber lining only); converter IP65.

11. Output signal: 4～20mA.DC, load resistance 0～750Ω.

12. Communication output: RS485 or CAN bus.

13. Electrical connection: M20×1.5 internal thread, φ10 cable hole.

14. Power supply voltage: 90～220V.AC, 24±10%V.DC.

15. Power consumption: ≤10VA.