Can an electromagnetic flowmeter show an out-of-range value?
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I would like to consult an instrumentation expert. There is an electromagnetic flowmeter installed on the pipeline, with a measurement range of 0–40. The rated flow rate of the pump is 40 m3/h, yet while the pump is operating, the flowmeter shows a flow rate of 47.8 m3/h. Can the electromagnetic flowmeter display a value of 47.8 m3/h when it is outside its specified range? Is this value of 47.8 reliable?
This situation is similar to using a ruler with a 20 cm scale to measure the length of an A4 sheet of paper; if you end up seeing the 29.7 cm mark on the ruler, it’s clear that this is impossible. 】So it feels incomprehensible. 【So I suspect: what you see (0~40 is incorrect); the range of the electromagnetic flowmeter should be around 60. The control room has changed the program, and now the range is 0~60. Therefore, the value of 47.83 that you see is likely accurate.】 】
The term ‘range’ has two meanings: the first is the range that the instrument itself can measure, and the second is the set range for the 4-20mA output of the instrument. The first is that inaccuracies occur when physical limits are exceeded; the second is that errors appear once manually set limits are surpassed. What you call the range resembles the second type, because the first type is generally not a whole number. So your display might be normal, and you need to change the settings of the instrument and the host computer.
:Victory: The second floor is the correct answer; you can go to the settings of the electromagnetic flowmeter to check the 4–20mA range settings