Loop Diagnostics when powering a positioner and taking measurements
Figure 4-2:
A.
The voltage measured at the HART or HART + pwr terminals
B.
Enable/disable the Trex unit to provide power to a transmitter or power and source current to a
positioner. This lets you isolate a problematic device from its HART loop and verify its operation.
Use the HART + pwr terminals on the Trex unit.
C.
Enable/disable the Trex unit to control current to an externally-powered positioner or to an analog
input card on a digital control system. The Trex unit controls current the same way as a
transmitter. Use the HART terminals on the Trex unit when the
Trex Unit Power
option is off. This
option is automatically enabled if
Trex Unit Power
is on and the Trex unit is powering a positioner.
D.
Change the settings for supplying/controlling current, including the values of the quick buttons, the
scale for the up and down arrows, and the time to change to a new current value. This option is
enabled only when
Trex Unit Power
or
Trex Unit Current
is on.
E.
The quick buttons to control the current to the positioner or 4-20 mA current loop. You can change
the values of the buttons from the
More Options
button.
F.
The current measured at the mA, HART + pwr, or HART terminals on the Trex unit. If
Trex Unit Power
is off and
Trex Unit Current
is on, use the HART terminals to measure current.
G.
The terminals that are controlling/measuring current and voltage are circled in green. Tap the
image to see a larger version.
H.
The current that the Trex unit is supplying.
I.
The up and down arrows to gradually increase or decrease the current. The default increment is
0.10 mA. You can change this increment from
More Options
.
J.
Tap the pencil icon to enter a new current value to be supplied.
Loop Diagnostics application
126
User Guide
Summary of Contents for AMS Trex
Page 1: ...User Guide Rev 3 August 2017 AMS Trex Device Communicator User Guide ...
Page 8: ...Contents vi User Guide ...
Page 130: ...Field Communicator application 122 User Guide ...
Page 186: ...Fieldbus Diagnostics application 178 User Guide ...
Page 198: ...Technical specifications 190 User Guide ...
Page 206: ...Glossary 198 User Guide ...