Ams trex™ Device Communicator

Figure 5-5: Connection for powering a FOUNDATION fieldbus device
A. FOUNDATION fieldbus Power Plug
3. On the 
Fieldbus Diagnostics Overview
screen, tap 
Power Supply
to enable power
to the device.
The Trex unit powers the device.
4. To stop power, tap 
Power Supply
or disconnect the lead set from the Trex unit.
5.6
Connect to an externally-powered fieldbus
segment
You can connect the Trex unit at various points, including at the device terminals or a
point along the fieldbus segment. The example below is for connecting to the fieldbus
segment to take measurements in the Fieldbus Diagnostics application.
Fieldbus Diagnostics application
User Guide
September 2021
160
User Guide

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Procedure
1. Connect the lead set to the FF terminals on the Trex unit and to the fieldbus
segment or device.
Figure 5-6: One connection option for connecting to the fieldbus segment
A. Terminators
B. Power conditioner
C. Fieldbus power supply
D. Host system
2. Open 
Fieldbus Diagnostics
.
The Trex unit connects to the device/fieldbus segment and begins the
measurements.
3. Optional - Tap 
Go Online
to query devices for their tags.
5.7
Measure the DC voltage, noise, and the
fieldbus signal
The Fieldbus Diagnostics Overview screen displays a GOOD, BAD, or CHECK status for the
measurements to give you a quick summary. Check the measurement criteria in the
Settings
to ensure they are appropriate for your installation.
You can view the actual measurement values by tapping Details on the Fieldbus
Diagnostics Overview screen.
Note
Before taking a noise measurement, remove the AC adapter from the Trex unit, if it is
connected. This isolates the Trex unit from the local power grid.
Procedure
1. If the FOUNDATION fieldbus device is externally-powered, do the following:
a) Connect the lead set to the FF terminals on the Trex unit and to the fieldbus
segment or device.
User Guide 
Fieldbus Diagnostics application
September 2021
User Guide 
161

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b) Open 
Fieldbus Diagnostics
.
The measurement status appears on the screen.
c) If the signal measurement status is "INACTIVE" or if you want to identify the
device tags that are listed on the Details screen, tap 
Go Online
.
2. If the FOUNDATION fieldbus device is not powered, do the following:
a) 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.
b) Connect the FOUNDATION fieldbus Power Plug to the FF pwr terminal and
the positive (red) FF terminal on the lead set.
c) Open 
Fieldbus Diagnostics
.
d) On the Fieldbus Diagnostics Overview screen, tap 
Power supply
to enable
power to the device. The Trex unit powers the device.
e) If the signal measurement status is "INACTIVE" or if you want to identify the
device tags that are listed on the 
Details
screen, tap 
Go Online
.