Figure 4-8: Connect to an externally-powered positioner in-series
The Trex unit controls current from the HART terminals.
A. Voltage source
Figure 4-9: Control current to simulate a transmitter on an externally-powered loop
The Trex unit controls current from the HART terminals, which simulates a transmitter.
The Trex unit controls current the same way as a transmitter controls current. The Trex
unit is connected to the analog input (AI) channel.
You can connect the Trex unit at various points on the current loop, including a junction
box, device connection point, etc.
A. Analog input
Loop Diagnostics application User Guide
September 2021
136 User Guide
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