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2. Operations
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Press / to view the HART parameters, and press / to open the setting status.
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In the setting status press / to select and press / to set.
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If the operation is canceled or fails, the value of the parameter will be reset.
3.2.4 Service
1. Loop test
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Select the predefined value or manually input a value, the range is (4~20) mA, and press / to test. The
ADT761 will then provide a mA source to the transmitter of the selected value. It will then read back the loop in real
time next to the term Loop mA.
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The Loop test is not available when the HART device is in multi-drop mode. All Field Devices must be able to operate
in multi-drop with loop current signaling disabled according to the HART Protocol.
2. D/A output trim
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Through adjusting the coefficient of current output, the transmitter`s PVAO is consistent with loop mA.
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Press / to trim the Zero (DAC Zero) and Span (DAC Gain), or press to put the mA value
measured by calibrator into the Trim Value input box. The range is (4~20) mA.
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The trim is not available when the hart device is in multi-drop mode. All Field Devices must be able to operate in
multi-drop with loop current signaling disabled according to the HART Protocol.
3. Zero trim
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Reduce the measure to near zero to avoid failure.
4. Re-Range
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Support to change the PV/Range unit and pressurize mode (internal pressure source or external pressure source).
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Test the pressure transmitter and change the range to adjust the shift of the output current.
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Press / to change the LRV/URV, or press to put the PV value into the New LRV/URV input box.
5. Sensor Trim
