Ams trex™ Device Communicator

Automatically generated file names
You can enter a file name for the log file or have the Fieldbus Diagnostics application
generate one based on the device tag or the device ID of the host and devices found on
the fieldbus segment. You must tap the 
Go Online
option before enabling logging to
automatically generate the file name.
Note
If multiple devices are on the fieldbus segment, the device or host system with the lowest
address is chosen for the file name. (Typically, the fieldbus host system has the lowest
address.) You can also enter a file name.
Displayed data
Each row represents a snap-shot in time when the measurement was taken and displays
the values for the DC voltage, noise, and signal measurements. The DC voltage
measurement value is displayed. The noise levels are divided by frequency into multiple
columns, and the value in the row is the measurement value in mV (peak-to-peak). The
signal measurements are organized by valid fieldbus address (16 -255), one column for
each address. The value in each column is the measurement value in mV (peak-to-peak).
Scroll to the right to see all columns in the log file.
Fieldbus Diagnostics application
User Guide
September 2021
170
User Guide

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Figure 5-10: Example log file
Measurement intervals
The Target Update Rate you set when you enable logging determines how many seconds
occur between the sets of measurements, up to the maximum number of log entries you
specify. The default is to take a DC voltage, noise, and signal measurement every 10
seconds up to 1,000 times. After 1,000 sets of measurements, the Fieldbus Diagnostics
application turns off logging and stops saving measurements.
The measurements may be taken more frequently than the number you set for the Target
Update Rate. If the Fieldbus Diagnostics application detects a device was added/removed
or it detects a bad DC voltage, the application captures an extra measurement "row" in the
log file to show the drop in voltage. The application attempts to take more data to help
you troubleshoot and determine the cause of the readings.
Note
The actual update rate may be affected by conditions on the fieldbus network. For
example, if the fieldbus network has a lot of scheduled activity, the rotation of the network
token will be slow, and the Trex unit will to wait longer to measure each device's signal.