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The daily maintenance of the electromagnetic flowmeter should be introduced

Doing a good job of daily maintenance can not only bring benefits to the normal operation of the machine, but also have an ideal effect on extending the service life of the machine. The electromagnetic flowmeter also needs daily or regular maintenance work, only when it is maintained. When the work is done and the details are done, the machine equipment can be better for the enterprise and the output for personal production.

Maintenance and daily maintenance of electromagnetic flowmeter:
The electromagnetic flowmeter only needs to periodically check the instrument for visual inspection, 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.
Electromagnetic flowmeter 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.

Electromagnetic flowmeter sensor inspection
Test equipment: one 500MΩ insulation resistance tester, one multimeter.

Electromagnetic flowmeter test steps:
(1) When the pipe 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.

Electromagnetic flowmeter converter check
If it is determined that the converter is faulty, if there is no problem in checking the external cause, please contact the manufacturer of the electromagnetic flowmeter. The manufacturer will generally solve the problem by replacing the circuit board.

Electromagnetic flowmeter notes:
1. Try to avoid ferromagnetic objects and equipment with strong electromagnetic fields to prevent the magnetic field from affecting the working magnetic field and flow signal of the sensor.
2. It should be installed in a dry and ventilated place as much as possible to avoid sun and rain. The ambient temperature should be -20 ~ +60 ° C, and the relative humidity is less than 85%.
3. There should be plenty of space around the flow meter for easy installation and maintenance.

Electromagnetic flowmeter installation requirements:
The measurement principle of the electromagnetic flowmeter does 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 before and after
b. Using a flow stabilizer
c. Reduce the cross section of the measuring point.

1. Requirements for the external environment
1. The flowmeter should be installed in a place where the temperature changes greatly or is subject to high temperature radiation from the equipment. If it must be installed, it must be insulated and ventilated.
2. The flowmeter is preferably installed indoors. If it must be installed outdoors, it should be protected from rainwater, flooded water and sun exposure. It must be protected from moisture and sun.
3. The flowmeter should be installed in an environment containing corrosive gases and must be installed when ventilation is required.
4. For installation, maintenance and maintenance, there is ample installation space around the flowmeter.
5. The installation site of the flowmeter should avoid magnetic fields and strong vibration sources. For example, if the pipeline vibrates greatly, there should be a fixed pipe support on both sides of the flowmeter.

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