Ams trex™ Device Communicator

Quick ad-hoc network tests to isolate issues
You can use the Trex unit to connect to various connection points on the fieldbus segment
to isolate an issue. For example, if the device fails to power due to a low-voltage at its
terminals, use the Fieldbus Diagnostics application to measure the voltage at all cable
connection points between the power supply and the device. These measurements can
help you identify the section of cable or junction box where the voltage drop occurs.
Long-term tests to catch sporadic issues
If a device has issues for only part of the day, you can take measurements over a period of
time to capture the time/date the issue occurs. For example, if you notice sporadic
increases in noise, you can take a measurement for multiple hours to determine when the
issue is occurring. This can help you relate the noise with another event, such as a variable-
frequency drive starting and stopping throughout the day.
Periodic tests to help you track your network and create trends
You can take measurements every few months to create an overall trend/report for the
fieldbus segment. For example, you can create one set of measurements when a device is
installed, and another set of measurements a year later for comparison. This can help you
track any slow degradation of the fieldbus segment.
The Fieldbus Diagnostics application has a logging feature that lets you save one or more
sets of measurements to a comma-separated values (.csv) log file. The files can then be
transferred to a PC for further review and analysis in a spreadsheet program.
User Guide 
Fieldbus Diagnostics application
September 2021
User Guide 
151

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5.1
Open or close the Fieldbus Diagnostics
application
Procedure
1. To open Fieldbus Diagnostics, tap the Fieldbus Diagnostics icon on the Trex 
Home
screen.
2. To close Fieldbus Diagnostics, tap 
Exit
.