ZWRY series intelligent electromagnetic flowmeter consists of two parts -- sensor and converter. It works based on the Faraday's law of electromagnetic induction. It is used to measure the volume flow rate of conductive liquid whose conductivity is greater than 5uS/cm. It is an inductive instrument for measuring the volume flow rate of conductive medium. In addition to measuring the volume flow rate of general conductive liquid, it can also be used to measure the volume flow rate of strongly corrosive liquids such as strong acid and alkali, and liquid-solid suspension liquids such as slurry, ore pulp and paper pulp. It is widely used for the flow measurement in petroleum, chemical, metallurgy, textile, paper, environmental protection, food and other industrial sectors, as well as municipal management, water conservancy construction, river dredging and other fields.
II. Working Principle
According to Faraday's principle of electromagnetic induction, a pair of detection electrodes are installed on the pipe wall where the axis of the measuring pipe is perpendicular to the magnetic force line. When the conductive liquid moves along the axis of the measuring pipe, the conductive liquid will cut the magnetic line so that to generate induced potential, which is detected by two detection electrodes. The value of the induced potential is proportional to the flow rate. The value is:
In the formula: E- induced potential
K - Coefficient related to magnetic field distribution and axial length;
B - Magnetic induction intensity
Y - Average flow velocity of conductive liquid
D - Distance between electrodes; (inner diameter of measuring pipe)
The sensor takes induced potential E as flow signal and transmits it to the converter. After a series of digital processing such as amplification, transformation and filtering, the instantaneous flow and cumulative flow shall be displayed by dot matrix liquid crystal with backlight. The converter has 4～20mA output, alarm output and frequency output, is equipped with communication interfaces such as RS-485, and supports HART and MODBUS protocols.
III. Product Characteristics
The measurement is not affected by the changes of fluid density, viscosity, temperature, pressure and conductivity.
There are no obstruction parts and no pressure loss in the measuring pipe, and the requirement of straight pipe section is low. It has unique adaptability for the measurement of slurry.
Reasonable selection of electrodes and lining materials, that is to provide the good corrosion resistance and wear resistance.
Full digital volume processing, with strong anti-interference ability, the measurement is reliable with high accuracy, and flow measurement range is up to 150:1
Ultra-low EMI switching power supply is suitable for wide range of power supply voltage variation and good anti-EMI performance.
By adopting 16-bit embedded microprocessor, the operation speed is fast, the accuracy is high, and the programmable frequency low frequency rectangular wave excitation improves the stability of flow measurement, and the power consumption is low.
Using SMD devices and surface mounting (SMT) technology, the reliability of the circuit is high.
There are no movable parts and no obstruction parts in the pipeline, and there is almost no additional pressure loss in the measurement.
The measurement range can be modified online according to the actual needs of users at site.
The measurement results have nothing to do with the physical parameters such as velocity distribution, fluid pressure, temperature, density and viscosity.
High definition backlight LCD display and full Chinese operation menu make it easy to be used and operated, as well as easy to be learned and understood.
Equipped with digital communication signal output such as RS485, RS232, Hart and Modbus Profibus-DP (optional).
It has the function of self-examination and self-diagnosis.
The hourly total volume recording function records the total flow volume in each hour, which is suitable for the time division metering system (optional).
There are three integrators equipped inside, which can display forward cumulant, reverse cumulant and differential cumulant respectively. There are material and electricity clocks equipped inside, which can record power failure time for 16 times (optional).
Infrared handheld manipulator, with 115KHZ communication rate, can be used to operate all functions of converter remotely and without contact (optional)