I. Product Overview:
LDE series electromagnetic flowmeter is an induction meter that measures the volume flow of conductive medium in the tube according to Faraday's law of electromagnetic induction. It adopts single-chip microcomputer embedded technology to realize digital excitation. At the same time, CAN field bus is used in the electromagnetic flowmeter. It can also output 4 ~ 20mA current signal for recording, adjusting and controlling. Besides the flow of general conductive liquid, it can also measure liquid solid two-phase flow, high viscosity liquid flow and volume flow of salt, strong acid and strong alkali liquid.
The integrated electromagnetic field is excited by constant current and low frequency three-valued rectangular wave or dual-frequency rectangular wave, which has the advantages of rectangular wave magnetic field and overcomes the disadvantages of sine wave magnetic field. Also can eliminate the power supply voltage fluctuation, power supply frequency change and excitation coil impedance change caused by the error; And has excellent zero stability and is not affected by fluid noise interference. Thus 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. The converter can be combined with the sensor and called a type flowmeter.
Split type electromagnetic design, convenient maintenance, increase the service life of electromagnetic flowmeter. Wall mounted flow converter, effective protection sensor conversion circuit, is conducive to corrosion, moisture, waterproof. The wiring is simple and installation is convenient. The split electromagnetic consists of a sensor mounted on a measuring pipe and a converter mounted within 30 meters or 100 meters from the sensor connected by a shielded cable to measure the volume flow of a conducting liquid. The main components of the sensor are measuring tube, electrode, excitation coil, iron core and magnetic yoke shell. It is mainly used to measure the volume flow of conductive liquid and grout in closed pipes.
Ii. Working principle:
LDE series electromagnetic flowmeter based on Faraday electromagnetic induction principle, with the sounding pipe axis and the magnetic field lines in the vertical tube wall installed on a pair of detecting electrodes, when conducting liquid along the measuring tube axis movement, conductive liquid cutting lines of magnetic force induced electric potential, the induction electric potential by two detection electrodes detection, numerical size and flow into a direct ratio, its value is: E = KBVD type:
E-induced potential;
K- coefficient related to magnetic field distribution and axial length;
B- magnetic induction intensity;
V- Average velocity of conductive liquid;
D- electrode spacing; (Measure tube diameter)
The sensor sends the induced potential E as a flow signal to the converter, which is amplified, transformed and filtered by a series of digital processing, and displays the instantaneous flow and cumulative flow with a backlit dot matrix LIQUID crystal. The converter has 4 ~ 20mA output, alarm output and frequency output, and has rS-485 communication interface, and support HART and MODBUS protocol.
Three, application:
LDE series electromagnetic flowmeters are mainly used to measure the volume flow of conductive liquid and slurry in closed pipes. Such as water, sewage, mud, paper pulp, all kinds of acid, alkali, salt solution, food slurry, widely used in petroleum, chemical, metallurgy, textile, food, pharmaceutical, papermaking and other industries as well as municipal management, water conservancy construction and other fields.
Iv. Structural form:
1. Sensor:
The sensor is mainly composed of measuring tube, measuring electrode, excitation coil, iron core, magnetic yoke and shell.
A. Measuring catheter: it is composed of stainless steel catheter, lining and connecting flange, and is the carrier for the field measurement of the liquid under test.
B. Measuring electrode: a pair of electrodes installed on the inner wall of the measuring tube, perpendicular to the direction of axial flow, so that the measuring liquid can produce signals.
C. Excitation coil: the upper and lower excitation coils that generate magnetic field in the measuring catheter.
D. Iron core and magnetic yoke: lead the magnetic field generated by the excitation coil into the liquid and form a magnetic loop.
E. Shell: instrument outer packing.
2, converter:
It is the intelligent secondary meter. After the flow signal is amplified and processed by the single-chip microcomputer, it can display the flow and accumulated amount, and output signals such as pulse and analog current, which are used for the measurement or control of fluid flow.
3. Product assembly form:
It can be divided into two forms: one body type and one body type.
A, one type: sensor and converter integrated installation.
B. Divider: the sensor and converter are separated and installed, and the flow metering system is formed by connecting the cable.
C, in order to adapt to the requirements of different media measurement, sensor lining and electrode materials can be a variety of choices.
Five, main features:
1, the instrument structure is simple, reliable, no moving parts, long working life;
2, no flow blocking parts, no pressure loss and fluid plugging phenomenon;
3, no mechanical inertia, fast response, good stability, can be used in automatic detection, adjustment and program control system;
4, the measurement accuracy is not affected by the type of measured medium and its temperature, viscosity, density, pressure and other physical parameters;
5. Different combinations of ptfe or rubber lining and Hc, Hb, 316L, Ti and other electrode materials can adapt to the needs of different media;
6, with pipe type, insert type and other types of flowmeter;
7, using EEPROM memory, measurement operation data storage protection safe and reliable;
8, with integration and separation of two types;
9, high definition LCD backlight display.
Vi. Technical Parameters:
1, instrument accuracy: pipe type 0.5, 1.0; Plug-in level 2.5.
2. Measurement medium: all kinds of liquid and liquid-solid two-phase fluid with conductivity greater than 5μS/cm.
3, flow rate range: 0.2 ~ 8m/s.
4. Working pressure: 1.6mpa.
5, ambient temperature: -40℃ ~ +50℃.
6, medium temperature: POLYtetrafluoroethylene lining ≤180℃; Rubber lining ≤65℃.
7, explosion-proof mark: Exmibd ⅱ BT4.
8. Explosion-proof certificate Number: GYB01349.
9, external magnetic interference: ≤400A/m.
10, shell protection: integrated type: IP65;
Separation type: sensor IP68 (5 m underwater, rubber lining only); Converter IP65.
11, output signal: 4 ~ 20mA.DC, load resistance 0 ~ 750 ω.
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.
