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Electromagnetic flowmeter sensing signal weakly susceptible to noise effects

Because the electromagnetic flowmeter's sensing signal is weak, it is susceptible to noise. Therefore, the reference potential of the sensor and converter must be the same as the liquid to be tested and grounded together.
The function of installing a grounding ring or a grounding electrode on both sides of the electromagnetic meter is to establish the equipotential of the flowmeter housing and the liquid.

Ordinary metal pipe (generally no grounding ring is required)
When the pipe itself is well grounded, the ground wire can be omitted, but the housing must be connected to the liquid through the ground wire provided by the flowmeter.
Insulated pipes (plastic pipes, rubber-lined pipes, etc.)
A grounding ring (or grounding electrode) should be installed at both ends of the sensor and the measured medium should be shorted to the ground through the grounding wire.
Cathodic protection pipeline
The pipe flanges are connected by copper wires but must be insulated from the ground wire.
Note: When the sensor is installed in an insulated pipe, the grounding ring can be avoided.
connection
Wiring must be done in accordance with the legend and requirements of the Electromagnetic Flowmeter Installation Manual.
All cables must be sheathed with an outer diameter of 5 to 8 mm, the power cable is a 2-core sheathed cable (core cross-sectional area ≥ 0.75 mm2), and the signal cable is a 2-core shielded cable (core cross-sectional area ≥ 0.75 mm2).
After the wiring is completed, the cover and cable gland must be checked to prevent dust or water from entering. After wiring, the screw caps cannot be replaced to prevent water leakage or moisture.
When using the threading pipe in the field wiring, pay attention to the lower end of the threading pipe to leave the water outlet to prevent water from flowing into the flowmeter through the threading pipe.
The power supply attention is divided into AC 220V or DC 24V. Note the polarity of the power supply. A misconnection of the power supply will cause the instrument to malfunction or be damaged.
Connect the matching grounding wire to the upstream and downstream metal pipes to keep the sensor casing and the measured medium equipotential.
Note: The load resistance range is 1K~5K; the external power supply voltage range is 5~24V DC.

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