2. Measurements and analysis of diagnostic signals.
Do you select the optimal high frequency band of
vibration to form the envelope spectrum for each measurement? The question asked
by employees of the maintenance services of the Moscow railway.
The question is answered by
Yury A. Azovtsev:
No, for the comparison reasons this frequency band is selected
from the possible ones only once for each measurement point. Moreover, if the
diagnostical standard is generated for a group of similar units of several
machines, then the frequency band for all these similar units must be the same,
though for some units the vibration in this frequency band may not meet all the
requirements for envelope detector filter.