Analyzing Demodulation Data - Commtest Instruments vb Series Instrument Reference Manual

Setting up the demodulation measurement
•
From the Main Menu press
Menu.
•
Press
Demodulation Quick Setup on page 34).
OR
•
Press
Measurement Mode Menu.

Analyzing Demodulation Data

Measuring, recording and viewing data is exactly the same as for a
Frequency/Acceleration spectrum. The demodulation spectra can
also be transferred to Ascent and analyzed using the same
techniques as for normal spectra e.g. trend plots, alarms, fault
frequencies, bearings and gears.
The following are points to keep in mind when analyzing
demodulation data:
•
The appearance of bearing tones in the demodulated
spectrum, but not in the normal spectrum, is a good early
warning indicator. It often points to insufficient lubrication.
•
As the bearing deteriorates, the baseline noise level
increases and bearing tones develop running speed
sidebands.
•
In the final stages of bearing wear, the bearing tones may
become less prominent as cracks and pits become more
rounded and distributed over the race.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
to use the Demodulation Quick Setup Menu (see
then to set all parameters manually using the
to display the Measurement
Section 7: Advanced Operation 103