Rosemount 248, Reference Manual

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Reference Manual
00809-0100-4825, Rev BB
August 2005
3-9
Rosemount 248
Diagnostics and Service
Test Device
The Test Device command initiates a more extensive diagnostics routine than
that performed continuously by the transmitter. The Test Device menu lists the
following options:
• 1 Loop test verifies the output of the transmitter, the integrity of the
loop, and the operations of any recorders or similar devices installed in
the loop. See “Loop Test” below for more information.
• 2 Self Test initiates a transmitter self test. Error codes are displayed if
there is a problem.
• 3 Master Reset sends out a command that restarts and tests the
transmitter. A master reset is like briefly powering down the transmitter.
Configuration data remains unchanged after a master reset.
• 4 Status lists error codes. ON indicates a problem, and OFF means
there are no problems.
Loop Test
The Loop Test command verifies the output of the transmitter, the integrity of
the loop, and the operations of any recorders or similar devices installed in the
loop. To initiate a loop test, perform the following procedure:
1. Connect a reference meter to the transmitter. To do so, shunt
the transmitter power through the meter at some point in the loop.
2. From the HOME screen, select 1 Device Setup , 2 Diag/Serv , 1 Test
Device , 1 Loop Test before performing a loop test.
3. Select a discreet milliampere level for the transmitter to output. At the
CHOOSE ANALOG OUTPUT prompt, select 1 4mA , 2 20mA , or
select 3 other to manually input a value between 4 and 20 mA.
4. Check the current meter installed in the test loop to verify that it reads
the value that was commanded to output. If the readings do not
match, either the transmitter requires an output trim or the current
meter is malfunctioning.
After completing the test procedure, the display returns to the loop test screen
and another output value can be chosen.
Master Reset
Master Reset resets the electronics without actually powering down the unit. It
does not return the transmitter to the original factory configuration.
Fast Key Sequence 1, 2, 1
Fast Key Sequence 1, 2, 1, 1
Fast Key Sequence 1, 2, 1, 3