What is the reason why an electromagnetic flowmeter shows a negative value during installation and use?

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　　Electromagnetic flowmeters are widely used in both industrial and domestic fields today; they are the most common type of flowmeter used for measuring conductive liquids, and their application is quite widespread. So what are the reasons why an electromagnetic flowmeter shows negative values during installation and use? 1. The sensor of the flowmeter was not installed in accordance with the direction indicated by the flow direction markers, resulting in the measurement being taken in the opposite direction. Solution: Reinstall. 　　2. The liquid to be measured inside the pipeline is not full; there is gas or bubbles present. At this time, the flow meter will display a negative value or the flow rate will fluctuate greatly. Solution: Ensure that the medium in the pipeline is at full level; the installation position of the flow meter can be adjusted, etc. 　　3. The signal wire of the flow meter sensor is connected reversely; since electromagnetic flow meters have the capability to measure flow in both directions, connecting the signal wire reversely will result in a negative value for the flow rate. Solution: Swap the connections of the signal wires. 　　4. The orientation set for the flow meter does not match the orientation indicated by the sensor. Solution: Reset the flow direction of the entire flowmeter converter. 　　5. There is magnetic field interference. Solution: Eliminate interference. 6. There is drift at zero point. Solution: Re-calibrate the zero point. 7. It is normal for a negative value to appear momentarily when the power supply is turned off, followed by a return to zero. This is because electromagnetic flowmeters have the capability to measure flow in both directions; when the flow direction is consistent with the direction indicated on the flowmeter, the value is positive, while it is negative otherwise. Under normal operation, when the flow direction matches the indicated direction, the instantaneous flow rate shows a positive value. However, when the pump stops, water may flow in the opposite direction, resulting in a negative value. The cumulative flow rate decreases as a result of the addition of positive and negative values, which is normal. If reverse measurement is not required, the two-way measurement function can be disabled. 　　After-sales service: For the first time of use, our technical engineers can go to the site to guide installation and debugging. Under normal use and within the warranty period, spare parts are replaced and repairs are carried out free of charge; upon receiving a call regarding a malfunction from the customer, if the issue cannot be resolved over the phone, a technician will be sent to the site within 48 hours (except in cases of force majeure). 　　We commit to: providing technical consultation on products; assisting customers in product selection; offering pre-sales, in-sales, and after-sales services; providing training on product usage; and delivering all services within our capabilities. For more information, please visit: http://www.hsdyb.com