View A Spectrum Of The Noise Measurement - Emerson AMS Trex User Manual

5.11.1

View a spectrum of the noise measurement

You can view the noise spectrum that displays the levels of low frequency (870 Hz - 9 KHz),
in-band (9 KHz - 39 KHz), and high frequency noise (39 - KHz - 100 KHz).
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.
Note
The spectrum measurement will fail if the noise amplitude exceeds 1.5 V (peak-to-peak). If you see
multiple high-amplitude noise peaks, look for an unattached wire that may cause high noise and
saturate the noise detection.
Procedure
1.
2.
User Guide
Connect to the FOUNDATION fieldbus device or segment.
On the Fieldbus Diagnostics Overview screen, tap Spectrum.
A spectrum displays the noise measurements. The highest peaks are outlined in
black.
Fieldbus Diagnostics application
165