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Electromagnetic flowmeter does not display flow failure analysis and processing steps

In the process of using the electromagnetic flowmeter, the electromagnetic flowmeter will be used just because of the installation error, the installation does not meet the requirements, the use error, the wiring error, the content of the case menu is disordered, the field interference is too strong, the waterproof sunscreen protection measures are improper, and so on. Problems soon occurred, or the service life was shortened, and such problems occurred after one year of use. In this paper, the electromagnetic flowmeter does not display the flow to analyze the cause of the fault and the processing steps.

The electromagnetic flowmeter does not display the flow failure.

1, wiring error

(1) Wiring. Before the electromagnetic flowmeter is connected, it should be confirmed that the installation orientation and direction are correct, and the site cleaning is carried out. The wiring of the electromagnetic flowmeter includes a connection of a power line, an input/output signal line, a sensing signal line, and a working ground line.

(2) Input/output signals. Most of the electromagnetic flowmeters can be programmed and detected by the external PLC, and can also accept the input commands of the main control system through the communication bus. Therefore, the electromagnetic flowmeter is provided with access points such as signal input contacts and measured value critical alarm commands. The output signal can be connected through the analog point, or combined with the output signal to connect to the PC through the RS-232 communication interface.

(3) Sensor connection. If the flowmeter and the sensor are installed separately, the flowmeter and the sensor need to be connected to pass the sensing current through the measuring terminal of the flowmeter (actually the magnetic pole and voltage measuring unit) to measure each Measuring parameters.

(4) Ground wire. Since the operating current of the electromagnetic flowmeter is small and is highly susceptible to interference from external electric field changes, the power supply and signal lines must be matched with a grounding wire to ensure accurate measurement data and eliminate frequent oscillations of data during the measurement process.

2, empty tube alarm <
The flowmeter pipe is not full, the electromagnetic flowmeter does not measure, or there is no fluid flow, and the flowmeter does not display the flow.

3, the range is not set correctly, or is confused, need to check

Second, the pipeline has flow but the electromagnetic flowmeter does not show what reason?
There are three reasons for this:
1, the display is not lit? First determine if there is no power? If the power supply is normal, the display does not light, indicating that the meter of the electromagnetic flowmeter has burned, or the display is broken, and it is necessary to return to the original factory for repair or replacement.
2, the display is bright, and can see the flow is worthwhile, there is fluid flow in the pipeline, but there is no normal flow, there are two cases, first, the flow is lower than the lower limit of the flowmeter calibration, the flowmeter can not measure small flow. Therefore, the normal flow value is not displayed. Second, if there is a problem with the internal settings, you can ask the original engineer to solve it.
3, the flow meter body into the water, resulting in the electrode can not work properly, there may be no display flow.

Third, the electromagnetic flowmeter does not display the flow value of another reason is: similar to the empty tube alarm bell flashing, may be the excitation fault, this need to first be an empty tube alarm, if the full tube is confirmed, then it may be the excitation fault, that is If the excitation line is faulty or the excitation line is in contact with the housing, the excitation line is in contact with the housing. In general, the excitation line failure may be caused by the field operator only removing the excitation line during the process of disassembling the head and then installing it. No flow display, display 0.

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