Accuracy issues of the instrument
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Everyone is welcome to participate in the discussion: 1. For a flow transmitter with an accuracy class of 0.25 and a process range of 0–7500 m3/h, the maximum absolute error during measurement is 52 m3/h. Is the accuracy of this instrument satisfactory?
Qualified. The maximum allowable error for a flow transmitter of class 0.25 is 0.25% of the range, that is, 7500 m3/h × 0.25% = 18.75 m3/h. However, the actual error of 52 m3/h is less than ±1.5% of the range, which is 7500 m3/h × 1.5% = 112.5 m3/h; therefore, the accuracy of the instrument is satisfactory. .
(1) The maximum allowable error is: 0.69% (2) The basic error is: 0.69% (3) The permitted error is: ±0.25%. Since the basic error of this instrument is 0.69%, which is greater than the permitted error of ±0.25%. The instrument accuracy is not up to standard.
Fail – the maximum allowable tolerance for this transmitter is ±18.75 m³/h, whereas the actual maximum value is 52 m³/h
What instrument? Calibrate the zero point before use
The instrument accuracy is not up to standard. Because the basic error of this gauge is 0.69%, which is greater than the allowable error of ±0.25% for the instrument.
Fail – the actual error is 0.69%, which is much higher than the theoretical maximum error of this flow meter
It would be better to first check whether this accuracy refers to the full-scale accuracy or the accuracy of the measured values. In certain ranges, there is basically no difference between these two levels of precision, but under extreme conditions, the difference in precision can be very large.