The MFC series electromagnetic flowmeters from Chuanyi show a reading of 0
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As the title says. An electromagnetic flowmeter from the MFC series, split-type, has been in use for over a year. Suddenly the traffic shows as 0, but there is actual traffic. The medium tested is domestic water. The sensor is sealed at the time of manufacture, and the converter is located inside the instrument box. Check that the wiring is normal, with no signs of water intrusion or rust. On-site measurement shows a voltage of over 40 millivolts between the signal wires SIG1 and SIG2. There is over 160 millivolts between SIG1, SIG2, and SIGGND. The resistance between the excitation coils CD1 and CD2 is 60 ohms. The wiring has good insulation. The converter was replaced again; the display fluctuated for a while before returning to 0 ； I really don’t know what the problem is now.
Let’s use Qingliu’s instruments instead; we have been manufacturing flow meters since 1958 as a state-owned enterprise, and we hope to have the opportunity to work together. If you have any technical issues, feel free to contact us at 15715320097
Based on the situation you described, the issue of the electromagnetic flowmeter showing a value of 0 may be due to one of the following potential reasons: 1. **Excitation coil problem**: The resistance between the excitation coils CD1 and CD2 is 60 ohms, which seems normal; however, if the excitation is insufficient or unstable, it can prevent proper flow measurement. It is recommended to check whether the excitation source is stable, and to ensure that the supply voltage and current meet the requirements. 2. **Signal detection issue**: The voltages between SIG1 and SIG2, as well as with respect to ground, as you mentioned, seem to indicate that a signal is indeed present, but it may be too weak or subject to interference. Check the signal cable for poor shielding or attenuation caused by long-distance transmission. At the same time, verify whether the signal processing circuit is in good condition, with no damaged or aged components. 3. **Converter failure**: Although you have replaced the converter, it still needs further verification to determine whether the new one is working stably. Sometimes, even newly converted converters may have defects or be incompatible with existing systems. 4. **Installation location or fluid condition issues**: Verify whether the flow meter is installed in an appropriate location, considering factors such as the installation angle and the presence of strong magnetic field interference. At the same time, ensure that the conductivity, temperature, pressure, and other conditions of the fluid being measured (domestic water) are within the operating range of the flow meter. In summary, it is recommended to systematically examine each component, especially the excitation section and the signal processing section. Confirm that all hardware connections are correct, the excitation source is stable, and all components are operating under the technically specified conditions. If the problem remains unresolved, consider contacting the device manufacturer for a detailed diagnosis or seeking professional technical support. .
Thank you. I will check it carefully again according to your instructions