Quotation for electromagnetic flowmeter for municipal engineering wastewater

1LDE sewage electromagnetic flowmetersummary:

The measurement principle of sewage flowmeter is Faraday's law of electromagnetic induction. The main components of the sensor are: measuring tube, electrode, excitation coil, iron core and magnetic yoke housing. It is mainly used to measure the volumetric flow rate of conductive liquids and slurries in closed pipelines. Including highly corrosive liquids such as acids, alkalis, salts, etc. This product is widely used in industries such as petroleum, chemical, metallurgical, textile, food, pharmaceutical, papermaking, as well as in fields such as environmental protection, municipal management, and water conservancy construction. The ZS-LD series electromagnetic flowmeter is a fully intelligent electromagnetic flowmeter developed using domestic and foreign technologies. Its all Chinese electromagnetic converter core adopts a high-speed medium * processor. The calculation speed is very fast, the accuracy is high, and the measurement performance is reliable. The converter circuit design adopts advanced technology, with an input impedance of up to 1015 ohms, a common mode rejection ratio better than 100db, and a suppression ability for external interference and 60Hz/50Hz interference better than 90db. It can measure fluid medium flow rates with lower conductivity. The sensor adopts non-uniform magnetic field technology and a special magnetic circuit structure, which makes the magnetic field stable and reliable, and greatly reduces the volume, reduces repetition, and makes the flowmeter small and flow oriented.

2、 Product features of LDE sewage electromagnetic flowmeter:

There are no movable parts or flow blocking components inside the pipeline, and there is almost no additional pressure loss during measurement.

The measurement results are independent of physical parameters such as flow velocity distribution, fluid pressure, temperature, density, viscosity, etc.

▲ The range can be modified online according to the actual needs of the user on site.

▲ High definition backlit LCD display, fully Chinese menu operation, easy to use, simple to operate, easy to learn and understand.

▲ Adopting SMD devices and surface mount technology (SMT circuits have high reliability).

Adopting a 16 bit embedded microprocessor, it has fast computing speed, high accuracy, programmable low-frequency rectangular wave excitation, improved stability of flow measurement, and low power consumption.

▲ All digital processing, strong anti-interference ability, reliable measurement, high accuracy, flow measurement range can reach 150:1

▲ Ultra low EMI switching power supply, with a wide range of power supply voltage changes and good EMC resistance

▲ There are three integrators inside that can display the forward cumulative amount and the difference cumulative amount respectively. There is also a non power down clock inside that can record 16 power down times

▲ It has digital communication signal outputs such as RS485, RS232, Hart, and Modbus.

3、 Working principle of LDE sewage electromagnetic flowmeter

The measurement principle is based on Faraday's law of electromagnetic induction. The measuring tube of the flowmeter is a non-magnetic alloy short tube lined with insulating material. Two electrodes are fixed on the measuring tube by passing through the tube wall along the diameter direction. The electrode tip is basically flush with the inner surface of the lining. When the excitation coil is excited by two pulse waves, a working magnetic field with a magnetic flux density of B will be generated in the direction perpendicular to the axis of the measuring tube. At this point, if a fluid with a certain conductivity flows through the measuring tube. Induce an electromotive force E by cutting the magnetic field lines. The electromotive force E is proportional to the magnetic flux density B. Measure the product of the inner diameter d of the tube and the average flow velocity v. The electromotive force E (flow signal) is detected by the electrode and sent to the converter through a cable. After amplifying and processing the flow signal, the converter can display the fluid flow rate and output signals such as pulses and analog currents for flow control and regulation.

E=KBdv

In the formula: E - -------------- is the signal voltage between the electrodes (v)

B - ----------------- Magnetic flux density (T)

D -----------------------------------------------------------------

V ---------------- Average flow velocity (m/s)

In the equation, k and d are constants. Since the excitation current is constant, B is also constant. Therefore, from E=KBdv, it can be seen that the volume flow rate Q is proportional to the signal voltage E -, that is, the signal voltage E induced by the flow velocity is linearly related to the volume Q. Therefore, as long as E is measured, the flow rate Q can be determined, which is the basic working principle of electromagnetic flow meters.

According to E=KBdv, parameters such as temperature, density, pressure, conductivity, and liquid-solid composition ratio of the measured flow medium will not affect the measurement results. As for the flow state, as long as it conforms to axisymmetric flow (such as laminar or turbulent flow), it will not affect the measurement results. Therefore, electromagnetic flowmeter is a true volumetric flowmeter. For manufacturers and users, the volumetric flow rate of any other conductive fluid medium can be measured without any correction as long as it is calibrated with ordinary water. This is a prominent advantage of electromagnetic flow meters, which is not found in any other flow meter. There are no active or obstructed components inside the measuring tube, so there is almost no pressure loss and high reliability.

Sewage flowmeterRelated parameter table:

Technical data of the whole machine and sensors

Technical Specifications:

● Nominal diameter series DN (mm)
Pipeline type PTFE lining: 10, 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600
Pipeline rubber lining: 40, 50, 65, 80, 100, 125, 150, 200, 300, 504, 500, 600, 800, 1000, 1200
Note: Special specifications can be customized
Flow direction: positive, negative, net flow,
Range ratio: 150:1
Repetitive error: ± 0.1% of the measured value
Accuracy level: Pipeline type: 0.5 level, 1.0 level
Temperature of the tested medium:
Ordinary rubber lining: -20~+60 ℃
High temperature rubber lining: -20~+90 ℃
PTFE lining: -30~+100 ℃
High temperature ethylene lining: -30~+180 ℃
Rated working pressure:
Pipeline type: DN10-DN65: ≤ 4.0Mpa, DN80-DN150: ≤ 2.5Mpa, DN200-DN1200: ≤ 1.6Mpa, special pressure range can be customized.
● Flow measurement range: The flow measurement range is 0.3-15m/s for flow velocity
Conductivity range: The conductivity of the measured fluid is ≥ 5 μ s/cm. Most media composed of water have a conductivity range of 200-800 μ s/cm, and electromagnetic flux can be used;
Output current and load resistance: 4~20mA Fully isolated load resistance ＜ 750 ohms Pulse frequency 0-1KHZ Optoelectronic isolation OCT External power supply ≤ 35V
When conducting, the maximum current at the collector is 25mA
Electrode materials: Stainless steel containing molybdenum, titanium (Ti), tantalum (Ta), Hastelloy (H), platinum (Pt) or other special electrode materials
● Protection level: Submersible type: IP68, other types IP65
Power supply: 85~265V, 45~63HZ
● Length of straight pipe section: Pipeline type: upstream ≥ 5DN, downstream ≥ 2DN
Connection method: The flowmeter and piping are connected by flanges, and the flange connection size should comply with the provisions of GB9119-88.
Anti riot sign: mdllBT4
● Environmental temperature: -25 ℃~+60 ℃
Relative temperature: 5%~95%
Total power consumption: less than 20W

Selection of LDE sewage electromagnetic flowmeter:

Note: 1. For plug-in type F, it means with installed ball valve and fittings. Without F, it does not come with a ball valve.