The electromagnetic flowmeter sensor housing protection grade is generally IP65 (international GB4208 enclosure protection grade - dustproof and bumper water level), please refer to Chapter 5, Section 5 for the installation location. The main requirements for the installation environment are:
(1) The sensor should be installed in a dry and ventilated place to avoid moisture, water and flooding, and direct sunlight and rainwater should be avoided.
(2) It should be avoided as much as possible in places where the ambient temperature is too high. The integrated structure of the electromagnetic flowmeter is also subject to the ambient temperature of the electronic components, which is lower.
(3) There should be no strong leakage current on the pipeline where the sensor is installed. It should be kept away from equipment with strong electromagnetic field, such as large electromechanical and large transformers, so as to avoid electromagnetic field interference;
(4) There should be no strong vibrations on the pipes or floors where the sensors are installed, especially integrated instruments;
(5) The location where the sensor is installed should take into account the space on site for maintenance.
The converter is used as a field installation instrument for on-site indication, and its installation site should generally choose:
The ambient temperature is between -10 and 45 °C;
The relative humidity of the air is ≤ 85%;
There is no strong vibration at the installation site;
The surrounding air does not contain corrosive gases;
The converter should be installed indoors as much as possible. When installing outdoors, measures against sun and rain should also be taken.
The selection of the instrument is a very important task in the application of the instrument. According to the relevant information, 2/3 of the faults in the actual application are caused by incorrect selection and incorrect installation of the electromagnetic flow meter, and special attention is paid.
(1) name of the fluid to be tested;
(2)maximum flow, minimum flow;
(3) working pressure;
(4)temperature, the lowest temperature.
• The fluid to be tested must have a certain conductivity, conductivity ≥ 5uS / cm.
• Maximum flow and minimum flow must meet the numbers in the table below. (Extension flow range 0.1~15m/s)
(1) Measurements are not affected by changes in fluid density, viscosity, temperature, pressure, and conductivity;
(2) There is no obstructive flow component in the measuring tube, no pressure loss, and the requirements of the straight pipe section are low;
(3)Series nominal diameter DN15 ~ DN3000. Sensor lining and electrode materials are available in a variety of options;
(4)The converter adopts novel excitation mode, low power consumption, stable zero point and high precision. The flow range can reach 1500:1;
(5) The converter can be integrated with the sensor or separated;
(6) The converter adopts 16-bit high-performance microprocessor, 2x16LCD display, convenient parameter setting and reliable programming;
(7) The flowmeter is a two-way measuring system with three totalizers: positive total, reverse total and total difference; can display. Zhuang, reverse flow, and has multiple outputs:
Stream, pulse, digital communication, HART;
(8) the converter uses surface mount technology (SMT), with self-test and self-diagnosis function;
According to the national standard GB4208-84 and the International Electrotechnical Commission standard IEC529-76, the standards for the degree of protection of the enclosure are:
• IP65: Waterproof type, allowing the faucet to spray water from the sensor in any direction. The water spray pressure is 30 kPa, the water output is 2.5 L/s, and the distance is 3 m.
• IP68: Diving type, working in the water for a long time.
The degree of protection should be selected according to the actual situation. The sensor is installed below the ground. If it is often flooded, IP68 should be used. If the sensor is installed above the ground, IP65 should be used.
The basic type of LDE electromagnetic flowmeter has functions such as display and output 4~20mA and 0~1kHz alarm, and other additional functions can be selected according to actual conditions.
• Separate installation: The sensor needs to be installed below the ground or for other reasons, and the split installation method should be selected.
• RS-485 communication requires sensors and other devices to communicate, you need to use RS-485 communication function.
Compared with other similar products abroad:
LDE-type intelligent electromagnetic flowmeter adopts a wide-temperature dot-matrix liquid crystal display with backlight. All displays are in Chinese. The functions are many and practical, which is especially convenient for users to operate, reducing unnecessary troubles and errors.
Fast delivery, low cost and easy maintenance.
LDE-type intelligent electromagnetic flowmeter is designed by our company with full intelligent principle. It has very different measurement accuracy, function, reliability and service life from the old or fake intelligent electromagnetic flowmeter produced by some domestic enterprises. .
The service life of the electromagnetic flowmeter should be more than 10-20 years, so we have fully considered the plant to this point in design. We are very careful from every detail of the sensor to the converter, from design, material selection, process, production. We are very particular about every aspect of testing and testing. We design and customize the production line of dedicated and electromagnetic flowmeters in China to ensure the long-term quality of our products.
The plug-in electromagnetic flowmeter is composed of a plug-in electromagnetic flow sensor (referred to as a sensor) and an electromagnetic flow converter (referred to as a converter) (referred to as a flow meter). It is a meter used to measure the volumetric flow of various conductive liquids in a pipe. Plug-in electromagnetic flowmeters are used to measure the flow of conductive fluids in tap water, steel, petroleum, chemical, electric power, industrial, water and other sectors, as well as corrosive conductive liquids such as acids, alkalis, and salts. Features:
(1), corrosion-resistant all stainless steel
(2), ABS full mold production probe
(3), the structure is simple, firm, no moving parts, long service life:
(4). Reliable measurement and strong anti-interference ability;
(5), small size, light weight, easy installation, small maintenance;
(6), the measurement range is large, the measurement is not affected by changes in temperature, density, pressure, viscosity, conductivity, etc.;
(7). The pressure loss is zero;
(8). It can be installed and disassembled under continuous flow, which brings convenience to the user's maintenance.
(9). Compared with the general electromagnetic flow meter, the manufacturing cost and installation cost are low, which is especially suitable for large and medium diameter pipeline flow measurement.
(1), the caliber of the pipe
(2), the name of the measured medium (must be a conductive liquid)
(3). Working pressure of the measured medium
(4), the working temperature of the measured medium
(5), the working flow of the measured medium
(6), whether with output and communication
(1 )When measuring the mixed phase fluid, choose the place that will not cause phase separation; when measuring the two-component liquid, avoid the downstream of the mixing that has not been uniformly mixed; when measuring the chemical reaction pipeline, it should be installed downstream of the fully completed reaction section; The straight pipe sections before and after are not less than 5D and 2D respectively;
(2) It is easy to realize the place where the sensor is grounded separately;
(3) Avoid high concentrations of corrosive gases in the surrounding environment as much as possible;
(4) To avoid the negative pressure inside the measuring tube;
(5) Avoid large motors and large transformers nearby to avoid electromagnetic field interference;
(6) Choose a place with small vibration, especially for integrated instruments;
(7) avoid direct sunlight
The measurement principle of the electromagnetic flow meterdoes not depend on the characteristics of the flow. If there is a certain turbulence and vortex in the pipeline, it will be generated in the non-measurement zone (such as elbow, tangential current limit or half-opening shut-off valve upstream). Nothing. If steady-state eddy currents in the measurement zone will affect the stability of the measurement and the accuracy of the measurement, then some measures should be taken to stabilize the flow rate distribution:
a. increase the length of the straight pipe section before and after;
b. using a flow stabilizer;
c. Reduce the cross section of the measuring point.
Upstream straight pipe section >10×DN
Downstream straight pipe section >5×DN
DN=sensor nominal diameter