Active Member
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[China]
Address: No.21, Lane 697, Guangfulin Road, Songjiang District, Shanghai, China
Contact name:Nancy Zhao
Melan Measurement & Control Instruments (Shanghai) Co.,Ltd. |
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China Water Electromagnetic Flowmeter Electro Magnetic Cheap Flow Meter
1.Working Principle
The principle of the sensor is based on Faraday’s law of electromagnetic induction.
It is installed a pair of detection electrodes on the pipe wall,where the measurement pipe axis
and magnetic field lines are vertical. When the conductive liquid cuts magnetic field lines and
produces induced electromagnetic force.Which can be measured by the two electrodes on the
meter pipe.The result can be calculated by formula: Induced electromotive force,(flow signal)
E=KBDV
E——Induced electromotive force,V；
K——meter constant；
B——Magnetic flux density,T；
D——Internal diameter of measuring pipe,m；
V——Average velocity of pipe section,m/s.
1MLF Series Electromagnetic Flow Meter
Assume the volume of liquid as qv(m3/s),qv=πD2V/4),so in the formula E=(4kB/πD)qv=kqv,
K is meter constant,K=4kB/πD.
Actually, the electromagnetic flow meter consists of two parts, transmitter and sensor, the
measuring electrodes inspect the electromotive force, and transmit to the converter, the
converter provides excitation current.
E is usually called a flow signal, after processing the flow signal by converter, output 4~20 mA/
pulse(or frequency) signal which is proportional to the flow rate, then the flow rate recording,
adjusting can be achieved.
2. Quick Details
MLF electromagnetic flowmeter is explosion-proof design.
Function of low conductivity measurement.
There are nine languages options to meet the needs of different customers.
It has the function of self-regulation and self-examination.
Different outputs are optional: Hart,RS485 Profibus,4-20mA, frequency, pulse.
3. Specification
| MLF Type | Divided Type | Integrated Type | Explosive Proof Integrated Type | Battery Powered Type | Heat Energy Type |
| Accuracy | ±0.2% or ±0.5% | ||||
| Pipeline Diameter | DN10-DN2000 | DN10-DN600 | DN25-DN2000 | ||
| Flange | GB, ANSI, JIS, BS, Others | ||||
| Pressure | DN10-DN600 1.0 1.6 2.5 4.0MPa | ||||
| DN700-DN2000 0.6 1.0 1.6MPa | |||||
| Liner Material | CR, PTFE, PU, Hard Rubber, PFA, FEP(F46) | ||||
| Conductivity | ≥5µs/cm(Please contact us if it is less than 5µs/cm) | ||||
| Electrode | 316L SS, Hb, Ta, Ti, Hc, Tungsten Carbide, Others | ||||
| Protection Class | IP65, IP66, IP67, IP68 | ||||
| Medium Temperature | -25~180℃ (Please refer to liner material) | -25~80℃(Please refer to liner material) | -25~180℃ (Please refer to liner material) | ||
| Ambient Temperature for Accuracy Influence | <±0.1%/10℃ or <±0.25%/10℃ at the ambient temperature of -25~60℃ | ||||
| Repetability | ≤±0.1% or ±0.25% | ||||
| Analog Output Error | ≤±0.02mA | ||||
| Velocity | 0.3~10m/s | ||||
| Electrical connection | M20x1.5 Seal Cartridge, GB1/2, NPT1/2 | ||||
| Output | 4-20mA, Pulse, RS485, Hart, Profibus | ||||
4. Selection of Liner Material
| Liner Material | Main Performance | Application |
| PTFE | 1. Have the most stable chemical properties in plastic and resistance to boiling hydrochlor and sulfuric acid, nitric acid aqua regia, strong alkali, and all kinds of organic solvents, but can not resist the corrosion of chlorine trifluoride, high temperature nitrogen trifluoride, liquid fluorine, liquid oxygen and ozone. 2. Low abrasion resistance. 3. Low negative pressure resistance | 1. -25~140℃ 2. Strong corrosion medium, like strong acid and alkali 3. Healthcare medium |
| CR | Oil proof, solvent resistance, oxidatite resistance and the resistance to the erosion of common medium like acid, alkali, salt, etc. | 1. ＜80℃ 2. Be able to measure sewage and mud |
| PU | 1. Very good abrasive resistance, flexibility. 2. Low acid and alkali resistance. | 1. ＜65℃ 2. Neutral strong abrasion resistance medium |
| Hard Rubber | 1 Resistance to room temperature, hydrochloric acid, acetic acid, oxalic acid, ammonia, phosphoric acid and 50% sulfuric acid, sodium hydroxide and potassium hydroxide 2 Avoid strong oxidants | 1. ＜80℃ 2. General acid, alkali, salt solution |
| PFA | 1. Can be used for most corrosive medium like acides, alkalis, and strong oxidant. 2. High material strength, resistance to aging, better than PTFE, EFP in high temperature 3. Injection molding for higher negative pressure | 1. 40~180℃ 2. Strong corrosion medium, like strong acid and alkali 3. Healthcare mdium |
| FEP(F46) | 1. Hydrophobicity and non-viscous 2. Corrosion resistance is inferior to PFA 3. Negative pressure | 1. 40~180℃ 2. Strong corrosion medium, like strong acid and alkali 3. Healthcare mdium |
5. Dimensional Sketches
a. Dimension of Converter
Divided Type
Integrated Type
Battery Powered Type
b. Dimension of Sensor
| Pipeline Diameter | Dimension | ||
| L | W | H | |
| 15 | 160 | 95 | 130 |
| 20 | 160 | 105 | 137 |
| 25 | 160 | 115 | 150 |
| 32 | 160 | 135 | 160 |
| 40 | 200 | 145 | 175 |
| 50 | 200 | 160 | 185 |
| 65 | 200 | 180 | 205 |
| 80 | 200 | 195 | 215 |
| 100 | 250 | 215 | 235 |
| 125 | 250 | 245 | 275 |
| 150 | 300 | 280 | 300 |
| 200 | 350 | 335 | 355 |
| 250 | 400 | 400 | 405 |
| 300 | 500 | 455 | 460 |
| 350 | 500 | 515 | 520 |
| 400 | 600 | 575 | 580 |
| 450 | 600 | 635 | 630 |
| 500 | 600 | 710 | 685 |
| 600 | 600 | 835 | 795 |
| 700 | 700 | 905 | 910 |
| 800 | 800 | 1020 | 1030 |
| 900 | 900 | 1120 | 1120 |
| 1000 | 1000 | 1245 | 1250 |
| 1200 | 1200 | 1465 | 1470 |
