Emerson AMS Trex User Manual page 142

Loop Diagnostics application
Figure 4-10:
The Trex unit is connected to an analog output and is measuring current from the mA terminals. You can
connect the Trex unit at various points on the current loop, including a junction box, device connection
point, etc.
WARNING!
Do not connect the mA terminals on the Trex unit to a power supply that is not current limited to
250 mA. This can blow a fuse inside the Trex unit. The repair/replacement will need to be completed
at an authorized service center.
A.
Figure 4-11:
A.
134
Read current for an analog output loop check
Analog output
Connect to an externally-powered positioner and read current
Analog output
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