Meriam MFT 4010 Modular Calibrator_HART Communicator - Manual (Page 71)

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LOOP TEST:
This option allows the user to send HART commands to the device under test to “fix” its analog output to
any desired value between 4 and 20 mA, regardless of process variable value.
This test is useful in determining the ability of a loop to deliver the accurate analog signals by providing a
specific current output to a receiving device.
Use the Down soft key to scroll to Loop Test and press the Select soft key to select. The screen will
prompt: Take Loop offline. This notice reminds the user that the device output will not be a measurement
of the actual process, and to place the receiving device or control system (such as a chart recorder, PLC, or
DCS) in manual mode. Press the OK soft key to continue. Press the Back soft key to return to the
Analog Trim main screen.
The MFT will execute the selected analog output assignment to the connected HART device and display
the results.
Messages relevant to Loop Test will appear in the message area shown above. This area will be blank if no
messages are issued by the HART device.
To set output automatically to desired value of 4, 8, 12, 16, 20mA select the corresponding key.
To manually change the fixed analog output value from the HART device, select “other” key. The following
screen will appear.
An underscore will prompt the user for changes ( _ ). Use the Inc / Dec soft keys to change the value and
the Next soft key to move to the next digit. When complete, press Done. A prompt will appear: Save new
data? Pressing No will take you back to the Loop Test main screen without making any changes. Press
Yes to accept the new value. The MFT returns to the Loop Test main screen. The message line will
indicate: “AO Fixed.”
The screen will display the prompt: Loop may be returned to automatic control. This notice reminds the
user to return the device to service. Press the OK soft key to continue. Press the Back soft key to return to
Hart
1151: Pump 8
Choose analog output level
-4mA
-8mA
-12mA
-16mA
-20mA
-Other
-End
Up Down Select Back
Hart
1151: Pump 8
_3.999mA
Inc Dec Next Back