Two-wire electromagnetic flowmeter was put into use

Recently, Yokogawa Electric announced the launch of the ADMAGAXR with excellent performance, which is the world's first two-wire electromagnetic flowmeter with dual-frequency excitation. So far, Yokogawa has only provided four-wire electromagnetic flowmeters with excellent performance. The addition of a new two-wire electromagnetic flowmeter to the product series can reduce installation and operating costs while ensuring high performance. In this regard, Yokogawa recently announced the launch of the ADMAGAXR with excellent performance, which is the world's first Two-wire electromagnetic flowmeter with dual-frequency excitation method. So far, Yokogawa has only provided four-wire electromagnetic flowmeters with excellent performance. The addition of a new two-wire electromagnetic flowmeter to the product series can reduce installation and operating costs while ensuring high performance. In this regard, Yokogawa has set the goal of obtaining the highest share of the global electromagnetic flowmeter market. The product is expected to go on sale in February 2009. Development background Electromagnetic flowmeters are used to measure the flow of conductive liquids such as water and chemicals. The most commonly used four-wire electromagnetic flowmeter is equipped with a dedicated power cable, which is separated from the signal cable used for current output to achieve high accuracy and performance. In contrast, the two-wire electromagnetic flowmeter uses only a pair of cables for current output and power supply. Since the two-wire system requires neither a dedicated power cable nor a power supply unit, the installation cost is significantly reduced. However, the traditional two-wire electromagnetic flowmeter cannot meet the minimum requirements for measurement accuracy and stability in the process automation field, and has not been widely recognized in the market. However, many companies need to reduce the cost of meters and hope that flowmeter suppliers can develop high-performance two-wire electromagnetic flowmeters. In order to meet this demand, Yokogawa has developed a new technology that can reduce the electrical noise of the two-wire system to the level of the four-wire system, thereby obtaining high measurement accuracy and stability comparable to the four-wire system. Market status of electromagnetic flowmeters In 2006, the global sales of electromagnetic flowmeters reached 730 million U.S. dollars. By 2011, it is expected to increase by 20% to 870 million U.S. dollars. These products can contribute to the construction of infrastructure in emerging countries, and maintain steady growth in equipment investment centered on chemicals, pharmaceuticals and power plants*¹. Although the previous two-wire electromagnetic flowmeter only accounted for a small part of the global market due to performance problems, the two-wire electromagnetic flowmeter with excellent performance developed this time will have a considerable development prospect once it is put on the market. Yokogawa is one of the largest suppliers in the global electromagnetic flowmeter market, with a market share of 12%*¹. Through the new products released this time, Yokogawa aims to gain 18% of the market share in 2010. Product features 1. Dual-frequency excitation The two-wire electromagnetic flowmeter adopts dual-frequency excitation, which can provide high measurement accuracy, stability and reliability for the use of control loops. The dual-frequency excitation method helps to improve stability, but due to the implementation of complex algorithms, it will increase power consumption. If this new technology is not developed, it is impossible to apply the dual-frequency excitation method to the two-wire electromagnetic flowmeter while ensuring high performance and low power consumption. Yokogawa introduced this technology in its new two-wire electromagnetic flowmeter. 2. New structure coil and noise reduction technology Due to the limited power supply capacity of the two-wire electromagnetic flowmeter, the current in the excitation coil is very weak, and it is difficult to distinguish the signal from the electrical noise. To solve this problem, Yokogawa adopted a new high-density coil structure that can generate a stronger magnetic field through low current. Yokogawa also found a way to reduce noise by smoothing the inner surface of the measuring tube and developing electrodes that produce little noise. Based on these efforts, the problem of distinguishing between signal and electrical noise was finally successfully solved, and measurement accuracy comparable to the four-wire system was obtained. 3. Easy to use The newly added full dot matrix LCD can display 6 languages; the electromagnetic switch can be operated without opening the cover; the diagnostic function of electrode attachment is increased; the design of the instrument orientation can be changed in the field, all of which are greatly improved User-friendliness. 4. Reduce installation and operating costs. This two-wire instrument no longer needs a dedicated power cable or a power supply unit, and the cost of the instrument is significantly reduced. Moreover, its low power consumption characteristics can also reduce operating costs. The main target market is widely used in the chemical, steel and food manufacturing industries to apply flow measurement-Reference-The measurement principle of electromagnetic flow meters The operation of electromagnetic flow meters is based on Faraday's Law, that is, conductive liquid flows through In the case of a magnetic field, the electromotive force generated by electromagnetic induction is proportional to the flow velocity. According to Fleming’s Right-hand Rule (Fleming’s Right-hand Rule), the direction of the electromotive force is at right angles to the direction of the liquid flow and the direction of the magnetic field. A pair of electrodes are installed in the measuring tube of the electromagnetic flowmeter, which can measure the generated electromotive force, calculate the flow rate, and then convert it into a unified 4-20mA current signal and pulse signal for output. This is one of the most accurate measurement methods in industrial flow meters. Moreover, there are no movable parts or obstacles in the measuring tube, and it can also be used for corrosive fluids and requires no maintenance. Therefore, electromagnetic flowmeters are widely used in industries such as chemical industry, food manufacturing, steel, papermaking, and water treatment. Characteristics of the dual-frequency excitation method The dual-frequency excitation method is Yokogawa's unique technology. In this way, it is possible to generate (excite) a magnetic field by passing currents with two high and low frequency components through the coil. The combination of the stability of low-frequency excitation and the noise suppression of high-frequency excitation enables this method to provide higher accuracy and stability than single-frequency excitation.