Ams trex™ Device Communicator

Figure 3-29: Power a HART transmitter
User Guide 
Field Communicator application
September 2021
User Guide 
85

---

Figure 3-30: Power a HART positioner
2. In the Field Communicator application, tap 
HART
.
3. Tap 
Yes
when prompted if you want the Trex unit to power the device.
4. Tap 
Transmitter
or 
Positioner
.
If you selected 
Positioner
, the Trex unit provides power and 4 mA.
5. Follow any additional prompts.
You may see additional prompts if the Trex unit cannot connect to the device. For
example, you may be prompted to review the polling address. For a positioner, you
may be asked to increase current (mA) to increase the value from the original 4 mA.
The Online menu or the device dashboard displays, depending on the device type.
Related information
Wiring diagrams for HART devices and the Field Communicator application
Wiring diagrams for the Smart Wireless THUM
™
 Adapter and the Field Communicator
application
Disconnect a device
HART communication terminals
Internal resistors
3.12.1
Power and connect to a Smart Wireless THUM adapter
The Trex unit must have the Device Communicator Plus communication module to power
a THUM adapter.
When performing a bench configuration, the THUM adapter should be attached to a
device. However, the Trex unit can power a THUM adapter when it is not connected to a
HART device.
To connect to a device that has a THUM adapter attached, see 
Connect to an externally-
powered HART device
or 
Power and connect to a HART device
.
 CAUTION
Remove the USB cable from the Trex unit before connecting to a device.
Field Communicator application
User Guide
September 2021
86
User Guide

---

Procedure
1. Connect the lead set to the HART + pwr terminals on the Trex unit and the red/black
wires on the THUM adapter.