To ensure the measurement accuracy of the electromagnetic flowmeter, proper installation is very important.
The transmitter should be installed in a dry and ventilated place indoors. Avoid installation in places where the ambient temperature is too high, should not be subject to strong vibration, try to avoid equipment with strong magnetic fields, such as large motors, transformers, etc. Avoid installation in corrosive gases. The installation location is easy to overhaul. This is the environmental condition to ensure the normal operation of the transmitter.
In order to ensure that the measuring tube of the transmitter is filled with the measured medium, the stacker is preferably installed vertically, and the flow direction is from bottom to top. Especially for liquid-solid two-phase flow, it must be installed vertically. If the site is only allowed to be installed horizontally, it must be ensured that the two electrodes are at the same level.
The transmitter should be equipped with valves and bypass at both ends.
The millivolt AC potential measured by the electrode of the electromagnetic flow transmitter is based on the liquid potential in the transmitter. In order to stabilize the liquid potential and maintain the potential of the transmitter and fluid to ensure stable measurement, the transmitter shell and the metal tube should have good grounding at both ends, and the converter housing should also be grounded. The grounding resistance should not be greater than 10 and cannot be shared with the grounding wire of other electrical equipment. If the transmitter housing is not guaranteed to be in good contact with the metal pipe, connect them with metal wires. Re-reliable grounding.
In order to avoid interference signals, the signal between the transmitter and the converter must be transmitted with shielded wires. It is not allowed to place the signal cable and power cable in parallel in the same cable. The length of the signal cable should generally not exceed 30 m.
Converter installation site should avoid AC and DC strong magnetic field and vibration, ambient temperature is -20 to 50 ° C, does not contain corrosive gases, relative humidity is not more than 80%.
In order to avoid the influence of the flow rate on the relative measurement, the flow regulating valve should be placed downstream of the transmitter. For small-caliber transmitters, since the distance from the center of the electrode to the inlet end of the flowmeter is equivalent to several times the length of the diameter D, the upstream straight pipe may not be specified. However, for a flowmeter with a large diameter, generally there should be a straight pipe section of 5D or more in the upstream, and the downstream pipe section is generally not required.
Main features of vortex flowmeter
Measuring medium: nominal diameter of liquid, gas and steam: DN15-DN300 (non-standard products can be customized according to user requirements) Temperature range: -40°C~350°C Pressure specification: PN1.6Mpa; PN2.5Mpa; PN4.0Mpa, Higher pressure specifications can be customized to a specific range: normal range 1:10 Extended range 1:15 Pressure loss factor: Cd ≤ 2.6 System measurement accuracy: liquid, gas indication ± 1%, steam indication ± 1.5% plug-in flow The measured value is ±2.5% of the supply voltage: sensor +12VDC, +24VDC (optional) transmitter +24VDC.
On-site display type The meter comes with 3.6 lithium battery output signal: sensor pulse frequency signal 0.1~3000Hz low level ≤1V high level ≥6V.
Transmitter two-wire 4~20mADC current signal for vibration acceleration: Piezoelectric ≤0.2g Ambient temperature: -40°C~55°C (non-explosion-proof place) -20°C~55°C (explosion-proof place) Ambient humidity: Relative Humidity 5~85% signal remote transmission distance: ≤500m signal line interface: internal thread M20×1.5 explosion-proof grade: iaIICT2-T5 protection grade: ordinary IP65 submersible IP68 instrument material: converter shell is made of aluminum alloy, the body part is adopted 1Cr18Ni9Ti can also be made of special materials according to user requirements.
Flow meter type
Instruments that measure fluid flow are collectively referred to as flow meters or flow meters. The flowmeter is one of the important instruments in industrial measurement. With the development of industrial production, the accuracy and range of flow measurement requirements are getting higher and higher, and the flow measurement technology is changing with each passing day. Various types of flow meters have been introduced to suit various applications. More than 100 flow meters have been put into use. From different perspectives, flow meters have different classification methods. There are two commonly used classification methods. One is to classify according to the measurement principle adopted by the flowmeter: the second is to classify according to the structural principle of the flowmeter.
Classified by flowmeter structure principle
A volumetric flow meter is equivalent to a standard volume container that measures the flow medium continuously. The larger the traffic, the more times the metric is, and the higher the frequency of the output. The principle of the volumetric flowmeter is relatively simple and suitable for measuring fluids with high viscosity and low Reynolds number. According to the shape of the rotary body, the products currently produced are: an oval gear flow meter suitable for measuring liquid flow, a lumbar flowmeter (Roots flowmeter), a rotary piston and a scraper flowmeter; a servo type suitable for measuring gas flow Volumetric flowmeters, membranes and flowmeters, etc.