The electromagnetic flowmeter has a large measuring range, usually 20:1~50:1, and the optional flow range is wide; the diameter of the electromagnetic flowmeter is wider than other types of flowmeters, from a few millimeters to 3 meters; the positive and negative two-way flow can be measured. The pulsating flow rate can also be measured as long as the pulsation frequency is much lower than the excitation frequency; the meter output is linear in nature; it is easy to select the material type of the fluid contact member, and can be applied to corrosive fluids and the like. Since the electromagnetic flowmeter measures much more with suspended solids or dirt than other flow meters, the probability of failure of the inner wall adhesion layer is relatively high. If the electrical conductivity of the adhesion layer is close to the liquid conductivity, the instrument can output the signal normally, but only change the flow area to form a hidden fault of the measurement error; if it is a high conductivity adhesion layer, the electromotive force between the electrodes will be short-circuited; if it is an insulating adhesion layer The surface of the electrode is insulated to disconnect the measuring circuit. The latter two phenomena will make the meter inoperable.
Ultrasonic flowmeter performance characteristics
Measuring liquid: single fluid such as water, seawater, alkali, etc., turbidity less than 10000ppm, particle size less than 1mm
Pipe material: Ultrasonic penetrating full pipe such as steel, cast iron, PVC pipe, dense texture, no serious corrosion and scaling, allowing thin layer of dense lining
Pipe lining material: rubber, epoxy asphalt, fiberglass, mortar, etc., or unlined
Pipe diameter range: DN15mm~6000mm, plug-in sensor for pipe diameter DN25mm~6000mm
Flow rate range: -32m/s~0~+32m/s, bidirectional flow
Accuracy: ±1.0% of displayed value (under standard conditions). Configure plug-in sensor accuracy up to 0.5%
Signal output: 4-20mA or 0-20mA RS-485
Sensor: It is divided into external clip type and plug-in type. The standard configuration is clip-on. The maximum operating pressure of the plug-in sensor is 3 MPa.
Straight pipe length: upstream >10D, downstream >5D from pump outlet >30D (D: pipe diameter)
Display mode: 2*20 character LCD display with LED backlight
Protection level: IP65
Explosion-proof grade: ExdIIBT4
Fixed ultrasonic flowmeter power supply: AC110V, AC220V, DC8~36V or AC7~30V
Ambient temperature / humidity: Host -20 ° C ~ +80 ° C; sensor -20 ° C ~ +80 ° C or -20 ° C ~ +160 ° C optional, the sensor can be immersed in water, water depth less than 2m.
Maintenance of the turbine flowmeter sensor section:
1. Before the sensor is installed, use the mouth to blow or hand the impeller to make it rotate quickly to see if there is any display. Install the sensor when there is display. If there is no display, check the relevant parts and troubleshoot.
2. When using, keep the measured medium clean and free of impurities such as fibers and particles.
3. When the turbine flow sensor starts to use, the sensor should be slowly filled with the medium, and then the outlet valve should be opened (the valve should be installed at the back end of the flowmeter). It is forbidden to be impacted by the high-speed fluid when the sensor is in the mediumless state.
4. The maintenance period of the turbine flow sensor is generally half a year. When cleaning and cleaning, please be careful not to damage the parts in the measuring chamber, especially the impeller. Please be optimistic about the positional relationship between the guide and the impeller during assembly.
5. When the turbine flow sensor is not in use, the internal medium should be cleaned, and after drying, a protective cover is added at both ends of the sensor to prevent dust from entering, and then stored in a dry place.
6. The filter used in the turbine flowmeter should be cleaned regularly. When not in use, the internal medium should be cleaned. As with the sensor, add a dust jacket and store it in a dry place.