1 If we are doing a vibration analysis and we are looking fo

1.) If we are doing a vibration analysis and we are looking for bad belt drives we should see the frequency appear at what multiple(s) of the belt RPM?

Solution

Case 1:

If the  frequency of vibration is having the highest amplitude or magnitude then it is Predominant frequency

Case 2:

Vibration frequency=n*RPM

If n=1, then it is synchronous or fundamental frequency

If n=1/2, then it is sub-synchronous frequency

If n=2,3,....., then it is harmonic or order frequency

If n=1/2,1/3,......., then it is sub-harmonic frequency

So, we can say that it can have fundamental or fractional multiples or positive integer multiples of the belt RPM