Ams trex™ Device Communicator

Figure 3-41: Fieldbus Device List
3.19
Power and connect to a FOUNDATION fieldbus
device
The Trex unit can power one FOUNDATION fieldbus device. The Trex unit can provide
approximately 10 volts at 25 mA to power a FOUNDATION fieldbus device. (The Trex unit
will draw approximately 12 mA when it is online).
If you try to apply power from the Trex unit when the device is externally-powered, the
Field Communicator application prevents the Trex unit from supplying power. This
protects the Trex unit from damage.
Note
When the Trex unit powers a FOUNDATION fieldbus device, two internal terminators and a
power conditioner are applied. Ensure the device is not connected to a fieldbus segment,
even if the segment is unpowered.
User Guide 
Field Communicator application
September 2021
User Guide 
105

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 CAUTION
Remove the USB cable from the Trex unit before connecting to a device.
 WARNING
Do not add any external power to the device when the Trex unit is powering the device.
This can blow a fuse inside the Trex unit. The repair/replacement will need to be
completed at an authorized service center. Ensure the device is disconnected from the
loop/segment and no other wires are connected to the device before providing power
from the Trex unit.
Procedure
1. Connect the lead set to the FF terminals on the Trex unit and directly to the
communication terminals on the unpowered device. Ensure no other wires are
connected to the device and there is no power to the device. Do not attach to a
junction box.
2. Connect the FOUNDATION fieldbus Power Plug to the FF pwr terminal and the
positive (red) terminal on the lead set.
Figure 3-42: Connection for powering a FOUNDATION fieldbus device
A. FOUNDATION fieldbus Power Plug
3. Open the Field Communicator application.
4. Tap 
Fieldbus
.
5. Tap 
Yes
when prompted if you want to provide power to the device from the Trex
unit.
The Trex unit provides power and searches for connected devices to display on the
Device List.
6. From the 
Device List
, tap the desired device.
The device menu displays.
7. To stop powering the FOUNDATION fieldbus device, close the Field Communicator
application or remove the lead set.
Field Communicator application
User Guide
September 2021
106
User Guide

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