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The split-type electromagnetic flowmeter is based on Faraday’s law of electromagnetic induction and consists of a sensor and a converter. The sensor is installed in the measurement pipeline, while the converter is placed within 30 meters or 100 meters of the sensor; the two are connected by a shielded cable. The main components of a split-type electromagnetic flowmeter sensor are: the measurement tube, electrodes, excitation coil, core, and yoke housing. It is mainly used to measure the volumetric flow rate of conductive liquids and slurries in closed pipelines. Such as water, sewage, sludge, pulp, various acid, alkali, and salt solutions, as well as food slurries, it is widely used in industries such as petroleum, chemicals, metallurgy, textiles, food processing, pharmaceuticals, and papermaking, as well as in fields like environmental protection, municipal management, and water conservancy projects, for measuring conditions of high temperature, high humidity, and difficult access. Like ordinary electromagnetic flowmeters, split-type electromagnetic flowmeters also require regular maintenance, and there are specific techniques for repairing faults; these will be briefly explained below. I. Daily inspection and maintenance of split-type electromagnetic flowmeters 1. Regularly check the sensor’s power cable and transmission cable (or wires) for any signs of damage or aging, and take care to protect the rubber insulation covering the cables. 2. Regularly (usually every six months), wipe the electrode surface with a soft cloth to remove dirt or deposits. 3. Remove debris from the straight section upstream of the sensor. II. Fault diagnosis of split-type electromagnetic flowmeters 1. Output is present despite no liquid flow: Causes: (1) An open circuit in the signal transmission cable connecting to the converter ； (2) Open circuit in the connection from the signal cable to the electrode ； (3) Contamination of the electrode surface or deposition of an insulating layer ； (4) Poor grounding or open circuit. Solution: (1) Connect the cable properly ； (2) Turn on the sensor and reconnect it ； (3) Scrub the electrode surface ； (4) Connect the ground wire properly. 2. No output for liquid flow: Reason: (1) The two wires of the signal transmission cable between the converter are connected in reverse order ； (2) Power supply not connected or poor contact ； (3) There are leaks in the sensor instrument pipelines, enclosures, and end faces. Solution: (1) Remove the loose wire end ； (2) Connect the power supply properly and ensure good contact ； (3) Repair the sensor. 3. Unstable output of the electromagnetic flowmeter: Cause: (1) Unstable flow field ； (2) The liquid passing through the sensor contains gases and large solid particles ； (3) Loose electrical connection ； (4) Poor grounding ； (5) Electrode leakage. Solution: (1) Modify the pipes or install fake sensors ； (2) Normal phenomenon ； (3) Check the wiring and connect it properly ； (4) Connect the ground wire properly ； (5) Repair the sensor. 4. Excessive error: Cause: High zero point ； (2) Not fully filled with liquid ； (3) Excessive distortion of the power supply ； (4) Poor grounding. Solution: (1) Re-adjust the zero point ； (2) Improve pipeline conditions to ensure the sensor is always filled with liquid ； (3) Improve the power supply conditions to meet normal operating requirements ； (4) Connect the ground wire properly.