Electromagnetic flow meter

Electromagnetic flow meter

Product description:

ZRN-LDC electromagnetic flowmeter
Joined: 2008-08-15 16: 39: 12
∷ Product us ∷
ZRN-LDC series magnetic flowmeter is Beijing zhongrui instrument technology limited company adopts advanced technology research and development of intelligent Electromagnetic Flowmeter, electromagnetic converter of Chinese core features a high-speed central processing unit, speed, high precision, reliable performance. Converter circuit design using international advanced technology, the input impedance up to 1015Ohm, cmrr 100dB, which can measure the lower conductivity of fluid flow. Its sensors magnetic structure with non-uniform magnetic field technology, the magnetic field is stable and reliable. Customers ' buy the rest assured that, with peace of mind, service satisfaction ' is our goal.
The measuring principle is Faraday's law of electromagnetic induction sensor main components were: measuring tubes, electrodes, coil, the iron core and yoke shell. It is mainly used for measurement in closed conduits of conductive liquid and slurry in the volumetric flow rate. Including acid, alkali, salt and other corrosive liquids. Main production type electromagnetic flowmeter and shape electromagnetic flow meters are widely used in petroleum, chemical, metallurgy, textile, food, pharmaceutical, paper and other industries as well as environmental protection, municipal administration, water conservancy construction and other fields.
Flow measurement is not affected by the density of the fluid, the viscosity, temperature, pressure and electrical conductivity effects of changes in rates, and average velocity sensor voltage signal linear, high measuring accuracy.

Measurement of pipe within the unimpeded flow, so there is no additional pressure loss; Measuring pipe has no moving parts, so very long sensor life.

Due to the inductive voltage signal is formed in the entire space filled with magnetic fields, is on pipe containing, on average, therefore the sensor of straight pipe is short, length 5 times times the pipe diameter.

Sensor only liner and electrode contact with the liquid to be measured, as long as the reasonable choice of electrode and lining materials, corrosion and abrasion.

ZRN-LDC converter using the latest most advanced microcontroller (MCU) and surface mount technology (SMT), reliable performance, high accuracy, low power consumption, zero point stability, convenient parameter setting. Click on the Chinese display LCD, displays the cumulative flow, flow, flow rate, flow percentages, and so on. ZRN-LDC electromagnetic flowmeter for measurement in closed conduits of conductive liquid and slurry volume, such as clean water, sewage water, acid, alkali and salt solutions, slurries, pulp, pulp and liquid food.

Bi-directional measuring system, measurable positive flows, the reverse flow. Using a special production process and quality materials to ensure product performance remains stable for a long time.

Electromagnetic Flowmeter selection

Selection of instruments is a very important instrument, the data indicate that, the instrument in actual application in 2/3 fault is the meter error selection or caused by wrong installation, please pay special attention to.

Electromagnetic Flowmeter selection Instructions correctly is to ensure the use of the electromagnetic flowmeter Electromagnetic Flowmeter selection of prerequisites. Choose what kind of electromagnetic flow meter according to the measured fluid physical properties and chemical properties to determine, the size of Electromagnetic Flowmeter, flow rate range, lining materials, electrode materials and output currents, can adapt to nature and nature of the fluid to be measured and discharge requirements. Can measurement of fluid: by electromagnetic flowmeter of work principle known, can selection Electromagnetic Flowmeter measurement flow of fluid must is conductive of, strictly of said, except high temperature fluid zhiwai, as long as conductivity rate is greater than 5 μ/cm of any fluid are selection corresponding of electromagnetic flowmeter to measurement flow, so not conductive of gas, steam, oil class, acetone, material cannot selection Electromagnetic Flowmeter to measurement flow. Determine the diameter of the sensor: flow meter flow rate best in the context of 0.3-15m/s, diameter of the flowmeter can select pipe size consistent with the user. Instrument parts using the velocity falls below 0.3M/s the best local increase flow rate, use shrink tube: reducer cone angles less than 15oC, may be considered part of the straight pipe reducer. Type one or type separation option: type: live under better conditions, generally choose a body type, sensor and assembled into a whole.

Electrode material
Platinum alloys
Stainless steel-coated tungsten carbide
Liner material
Poly-fluorinated ethylene propylene F46
Vinyl Fluoride-FS
Poly recorded butyl rubber
Polyurethane rubber
0.3 levels
0.5 levels
1 levels
4-20Madc, load ≤ 750 ω
0-3khz; 5V source; Variable pulse width; Output high effective frequency
RS485 interface
Normal temperature
High temperature type
Ultra high temperature type
Body structure
Body structure
Explosion-proof type structure

• Data collection

① composition the biggest flow measured, ③ maximum working pressure minimum flow II maximum temperature, minimum temperature

Electromagnetic flowmeters Q range should be greater than the estimated maximum flow of value and value slightly larger than normal flow flowmeter full scale scale 50%.
Instrument selection
• Measuring range to confirm
Industrial magnetic flowmeter measured medium velocity 2~4m/s is appropriate, in exceptional circumstances, the minimum flow rate should be not less than 0.2m/s, the maximum should be not more than 8M/s.
If the medium contains solid particles, flow rate should be less than 3M/s, to prevent excessive friction lining and electrode; For viscous fluids, flow rate can be selected is greater than 2m/s.
Larger flow rates contribute to the automatic elimination of effects of electrodes attached to the sticky, helps to improve the measurement accuracy.
Quantum Q defined conditions; According to the size of the velocity v-scope-meter-diameter d; The calculated value is determined by the following formula:
Q=πD2V/ 4
Q: flow (㎡/h) d: pipe inside diameter v: velocity (m/h)
Electromagnetic flowmeters Q range should be greater than the estimated maximum flow of value and value slightly larger than normal flow flowmeter full scale scale 50%

The choice of installation place
In order for electromagnetic flowmeter is stable and reliable, when choosing the installation site should note the following requirements:
1. try to avoid magnetic objects and devices with strong electromagnetic fields (motors, transformers, etc), so as to avoid magnetic field sensors magnetic field of work and traffic signals.
2. to be installed in a dry and ventilated place, avoid the Sun and rain, the ambient temperature should be -20~+60 ℃, relative humidity is less than 85%.
3. flow meters there should be ample space around, easy to install and maintain.
Measurement of electromagnetic flowmeter principle does not rely on flow characteristics of pipe has a certain degree of turbulence and eddies generated in the non-measuring in the region (such as elbows, to open up the limit or stop valves) the measure is irrelevant. If you have steady Eddy current measuring area can affect the measurement stability and accuracy of measurement, then you should take a number of steps to stabilize the flow rate distribution:
A. increase the length of straight pipe before and after;
B. use a flow stabilizer;
C. reduce the measurement section.

Selection of electrode materials:

Corrosion resistance
Application: 1, domestic water, industrial water, water wells, sewage.
2; Weak corrosive acid; Alkali; Salt solutions
Hastelloy b
Application: 1 hydrochloric acid (concentration less than 10%), all concentrations of ammonium hydroxide solution
2, sodium hydroxide (concentration less than 50%), all concentrations of ammonium hydroxide solution
3; Phosphoric acid; Organic acid
Not applicable: hydrochloric acid
Hastelloy c
Apply: 1 mixed blend of acids, such as chromic acid and sulphuric acid solution
2; Oxidizing salts such as Fe++; Cu++; Sea water
Not applicable: hydrochloric acid
Titanium (Ti)
Application: 1; Salt; Such as: (1) chloride (chloride/ammonium/calcium/magnesium/aluminum/titanium)
(2) sodium salt; Potassium salt; Ammonium salt; Hypochlorite salts; Sea water
2; Potassium chloride hydrogen concentration is less than 50%; Ammonium hydroxide; Barium hydroxide solution
Not applicable: hydrochloric acid Sulfuric acid; Phosphoric acid; Hydrofluoric acid; Barium cyanide and alkali solution
Tantalum (Ta)
Application: 1 hydrochloric acid (concentration less than 40%), dilute sulfuric acid, and concentrated sulfuric acid (not including fuming sulfuric acid)
2; Chlorine dioxide; Magnesium chloride; Sodium hypochlorite; Sodium cyanide; Lead acetate
3, nitrate (including fuming nitric acid) and oxidizing acids, temperature less than 80 degrees of aqua regia
Not apply to alkali and hydrofluoric acid
Platinum (Pt)
Apply: almost all of the acid; Alkali; Salt solutions (including fuming sulfuric acid, fuming nitric acid)
Not applicable: Aqua, ammonium salt

Electromagnetic Flowmeter liner material options:

Should be based on the measured medium corrosion, abrasion and temperature to select lining material.

Liner material
The name
Maximum operating temperature
Apply liquid
Apply diameter
Chloroprene rubber
Medium wear resistance, corrosion resistance to low concentrations of acid, alkali and salt
Tap water; Industrial water; Sea water
Ammonium poly resin rubber
Excellent wear resistance, acid and poor performance
Pulp, pulp slurry
Fluorine plastic
Poly vinyl chloride
F4 or
Chemical stability; Resistance to boiling hydrochloric acid; Sulfuric acid; Aqua regia; Concentrated alkali corrosion
Strong acid, alkali and salt corrosion liquids
PCE and hexafluoropropylene
Translation: Teflon FEP
F46 or
Performance chemicals is less than F4
Liquid corrosive acid, alkali and salt
Perchloroethylene and ethylene
F4 or ETFE
Performance chemicals is less than F4
Liquid corrosive acid, alkali and salt
Chemical stability
Polyphenylene ether
Hot water

Choice of degrees of protection:
1, IP65: Blowout water, allowing the tap water spray from any direction on the sensor, water jet pressure 30kPa, water 12.5L/s, a distance of 3M.
2, IP68: diving, working in water for a long time.
Protection rating should be selected according to the actual situation; Sensor mounted below the surface; As has often been flooded; IP68, sensor is installed above ground, you should use IP65.

Selection of additional features
LDE-type basic type of intelligent electromagnetic flowmeter with display and output 4-20mA and 0-1kHz alarm function, according to the actual situation and other additional features.
3, split installation: the sensor should be installed below ground level, or other reasons, should choose the installation method.
4, RD-485 communication: communicate need for converters and other devices, you will need to use RS-485 function.