Electromagnetic flowmeter features
Frequency programmable low frequency rectangular wave excitation improves stability of flow measurement and low power loss.
The new 16-bit ultra-low power microprocessor with FLASH memory has high integration, fast calculation speed and high calculation accuracy.
Full digital processing, strong anti-interference ability and reliable measurement.
Ultra-low EMI switching power supply, suitable for power supply voltage variation range, high efficiency, small temperature rise; good EMC performance.
Chinese and English menu operation, easy to use, easy to operate, easy to learn and understand.
High definition backlight wide temperature LCD display.
It can perform bidirectional flow measurement and bidirectional total accumulation; it has automatic range switching function, which can effectively improve the measurement accuracy of analog current and frequency output, especially suitable for occasions where the diurnal flow range changes greatly and needs to send control signals; flow measurement range Up to 1500:1.
There are three totalizers inside, which record and display the forward cumulative amount, the reverse cumulative amount and the accumulated difference integrated amount, which are convenient for fluid metering and custody transfer.
Provide isolated or non-isolated RS485/RS232C digital communication interface, and support fieldbus communication modes such as MODBUS, PROFIBUS-DP and HART.
Constant current source fluid resistance measurement can accurately measure the internal resistance of the electrode signal in the case of long-line transmission. It can be used not only to determine whether the fluid in the sensor is empty or not, but also to identify abnormal phenomena such as contamination and coverage of the electrode, and to provide cleaning for the user. Fault processing information such as electrodes.
Ultrasonic flowmeter features
The unique signal digitization processing technology makes the meter measurement signal more stable, anti-interference ability and more accurate measurement.
No mechanical transmission parts are not easily damaged, maintenance-free and have a long service life.
The circuit is more optimized, with high integration, low power consumption and high reliability.
Intelligent standard signal output, friendly man-machine interface, multiple secondary signal output, for you to choose.
Pipe-section small pipe diameter measurement is economical and convenient, and the measurement accuracy is high.
Detailed installation of ultrasonic flowmeter
Ultrasonic flowmeters should be aware of the site prior to installation, including:
1. What is the distance from the host at the installation of the sensor;
2. Pipe material, pipe wall thickness and pipe diameter;
3. Years of pipeline;
4. The type of fluid, whether it contains impurities, bubbles and whether it is full;
5. Fluid temperature;
6. Whether there is interference source at the installation site (such as frequency conversion, strong magnetic field, etc.);
7. Four seasons temperature at the host place;
8. Whether the power supply voltage used is stable;
9. Do you need remote signals and types;
According to the site conditions provided above, the manufacturer can configure the site conditions and, if necessary, special models.
Daily maintenance (1)
Only need to periodically check the instrument, check the environment around the instrument, remove the dirt, ensure that no water and other substances are inspected, check whether the wiring is good, check whether there is a new strong electromagnetic field device near the instrument or a new installed wire across the instrument. If the measuring medium is easy to contaminate the electrode or precipitate or scale in the measuring tube wall, it should be regularly cleaned and cleaned.
Folding fault finding
After the flowmeter starts to be put into operation or is put into operation for a period of time, it is found that the instrument is not working properly. First, check the external condition of the flowmeter, such as whether the power supply is good, whether the pipeline is leaking or is in a state of non-full pipe, whether there is air bubble in the pipe, whether the signal cable is Damage, converter output signal (ie rear position meter input loop) is open circuit. Remember to blindly disassemble the flowmeter.
Sensor check
Test equipment: one 500MΩ insulation resistance tester, one multimeter.
Test steps:
(1) When the pipeline is filled with medium, measure the resistance between terminals A, B and C with a multimeter. The resistance between A-C and B-C should be equal. If the difference is more than 1 time, there may be leakage of the electrode, condensation on the outer wall of the measuring tube or the junction box.
(2) In the case of lining drying, measure the insulation resistance between A-C and B-C with MΩ meter (should be greater than 200MΩ). Then use a multimeter to measure the resistance of the two electrodes in terminals A and B and the measuring tube (should be in short-circuit communication). If the insulation resistance is small, indicating that the electrode is leaking, the entire flowmeter should be returned to the factory for repair. If the insulation is reduced but there is still more than 50 MΩ and the inspection result of step (1) is normal, the outer wall of the measuring tube may be damp, and the inside of the outer casing may be dried by a hot air blower.
(3) Use a multimeter to measure the resistance between X and Y. If it exceeds 200 Ω, the excitation coil and its lead wire may be open or poorly connected. Remove the terminal block check.
(4) Check the insulation resistance between X, Y and C, which should be above 200 MΩ. If it is lowered, dry the inside of the casing with hot air. In actual operation, the decrease in coil insulation will result in increased measurement error and unstable instrument output signal.
(5) If it is determined that the sensor is faulty, please contact the manufacturer of the electromagnetic flowmeter. The general site cannot be solved and needs to be repaired by the manufacturer.