Azbil PTG71, Руководство пользователя

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Azbil Corporation Calibration
Model PTG71 / 72 - Smart Pressure Transmitter 9-3
9-2 : Calibrating the set range by inputting the actual pressure
Overview
This section describes how to calibrate URV and LRV for the set range by inputting a
reference pressure into the Transmitter using the HART Communicator.
Calibrate the LRV first and then URV.
Calibration devices
Generally, the calibration devices listed below are required:
• Reference pressure generator : A generator capable of producing pressure over
a range of measurement close to that of the
transmitter to be tested.
• Accuracy : ± 0.05% F.S. or ± 0.1% (whichever is larger)
• Power supply : 24 V DC
• Standard resistor : 250
Ω
±0.005%
• Voltmeter : Digital voltmeter (10 V DC range) with an
accuracy of ±0.02% rdg + 1dgt
• HART Communicator
Requirements for calibration
CAUTION
When conducting the actual-pressure calibration, the following requirements must be
satisfied:
• The calibration must be conducted in a testing laboratory where there is no wind.
•
The standard temperature is 23°C {73°F} and the standard humidity is 65%.
Room temperatures from 15°C {59°F} to 35°C {95°F} and room humidity from
45% to 75% are acceptable as long as the result of measurement is not influenced.
• It is best if the accuracy of the measuring instruments to be four times greater
than that of the Transmitter.