OAT Order magnitude and phase vi problem

[Thiruveni]

while performing order analysis using OAT Order magnitude and phase vi the output Speed is less the input speed.When performing order analysis for vibration signals with the Speed profile values from 500 to 4500 rpm, the vibration signals are first passed to OAT Convert to even angle signal.vi then given to OAT Order magnitude and phase vi and X-axis selection is speed but the Output magnitude is from 1000 to 4000 RPM.but i want the magnitude values same as input speed 500 to 4500 RPM

[Bob_Schor]

It is so much easier to find the Errors (or Mis-conceptions) in a VI if we can see, poke around in, modify, test, etc. the actual VI.  Please attach your VI.  You appear to be using (I'm guessing here) the Sound and Vibration Toolkit -- it would be good to mention this (if true) in your Post, as 99% of the LabVIEW installations probably do not include this Toolkit.  I, for example, have no idea what "OAT Order Magnitude" means (though I certainly understand the concepts of "magnitude" and "phase").  Of course, I can "look it up", but a little bit of help from the Original Poster goes a long way ...

So (having looked it up), this is a Function from the Sound and Vibration Toolkit.  It has a lot of highly-specific Inputs.  When a complex function does not produce values that make sense with "real data", a useful tactic is to write a little VI that generates known "Test" data with known (simple) parameters and use this to test your understanding of the particular (OAT) function.  When you post your code, this is probably what some of us would be tempted to try ...

Bob Schor

[Thiruveni]

Thank you for the replay,yes i am using sound and vibration toolkit.

i have also attached the vi,and i have two main questions.

1.in input speed profile the rpm starts from 671 to 4514 rpm but the output magnitude speed is from 671 to 4501 ,why cant i get exact input rpm i.e..,4514.

2.what is minimum data requirement for OAT Order magnitude and Phase.vi and how is it calculated.

in sound and vibration toolkit user manual it is given that minimum data requirement is based on reset,Band width Order etc but how is it calculated.if i give minimum data error code 4961 is being displayed.

[Thiruveni]

Please somebody replay or suggest any other ideas..!

my main question is how the PPR,Order etc..,affect the minimum data requirement given to Order analysis vi's in sound and vibration Toolkit.