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Emerson mass flow meters and electromagnetic flow meters require a reliable grounding during installation in order to improve measurement accuracy and avoid interference from external electrical potentials. The sensors should have their own proper grounding, with the grounding resistance generally should be less than 10 ohms. If the pipe connecting the sensor is coated with an insulating layer or is made of a non-metallic material, grounding rings should be installed on both sides of the sensor. Attention should also be paid to the loop grounding and shielding grounding between sensors, converters, and secondary instruments. If the pipeline connecting the instrument is insulating (with respect to the medium being measured), a grounding ring is required. Common materials for grounding rings include 316L stainless steel, Hastelloy B and C, titanium, tantalum, platinum, etc. The material of the grounding ring should be suitable for the corrosivity of the medium being tested. Installation of Emerson flowmeter sensors on metal pipes. Sensors with insulating coatings on their inner walls are used for metal pipes, while they are installed on plastic pipes or pipes that have insulating coatings, paint, or linings. Grounding rings (or short tubes with grounding electrodes) should be installed at both ends of the sensor, so as to create a short circuit between the medium flowing inside the pipe and the ground, thereby ensuring a zero potential; otherwise, the electromagnetic flowmeter cannot function properly. The installation of sensors on cathodic protection pipelines: Pipelines protected against electrolytic corrosion are usually insulated on their inner or outer walls; as a result, the medium flowing within them does not have a grounded potential, and therefore sensors must be equipped with grounding rings. The grounding rings must be installed on the two end faces of the sensor; they must be insulated from the flanges of the connecting pipes, and connected to the sensor’s grounding ring through grounding. The material of the grounding rings should be resistant to corrosion by the medium. It is advisable to use copper wires with a cross-sectional area of 16 mm2 to connect the flanges on both sides of the sensor, thereby isolating the cathodic protection potential from the sensor. The working ground connection for Emerson flowmeters should adhere to the \"single-point grounding principle.\" The working grounding and shielding grounding between sensors, converters, and secondary instruments serve to ensure the accurate and reliable operation of these instruments, as well as to protect equipment and human safety.