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8-2
Chapter 8 Calibration
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Calibrating the Setting Range Using Standard Input (Input Calibration)
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Preparation
The following describes how to calibrate the lower range value (LRV) and upper range
value (URV) of the measuring range by inputting the standard pressure to this device. First,
calibrate the lower range value, and then calibrate the upper range value.
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Equipment
The following equipment is needed for this calibration. The required performance of each
device is described for reference purposes. It is desirable that the uncertainty of the instru-
ment is four times larger than the accuracy of the liquid level transmitter to be calibrated.
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Standard pressure generator (a generator that can generate the pressure of the measur-
ing range of this device)
Accuracy: ±0.04 % F.S. or better
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Power supply: 24 V DC
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Precision resistor: 250 Ω ± 0.005 %
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Voltmeter: 10 V DC range ± 0.02 % + 1 digit
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Communicator: CommStaff
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Caution
The accuracy of this device after calibration depends on the performance levels of the
devices used for the calibration.
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Calibration Conditions
The calibration of the actual pressure is performed under the environmental conditions
shown below.
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Calibrate in a windless testing laboratory. If there is wind, pressure is applied to the
pressure-receiving section where the hole open to the air is located, adversely affecting
calibration accuracy.
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Standard operating temperature 23 °C, humidity 65 %
If there are no sudden changes, there are no significant effects within the normal ranges
of 15 to 35 °C temperature and 45 to 75 % humidity.