Scaling of spectra
As described under Scaling of spectra, the Condition Monitoring library offers a number of different options for scaling of spectra. This tutorial enables examination of various prepared scalings by means of a simple sine wave, and to deepen the theoretical understanding. The scopes are limited to the range 0 Hz to 400 Hz, in order to be able to show the differences more clearly.
The tutorial is available for download from here:
SpectrumScaling_Sample.zip
Block diagram
Program parameters
The table below shows a list of important parameters for the configuration of the used function blocks FB_CMA_MagnitudeSpectrum and FB_CMA_PowerSpectrum.
GVL_Constant contains three scenarios, which you can test by commenting or uncommenting the selected code segments and enabling the configuration. The expected behavior of the scenarios is documented in the GVL as a comment.
FFT length | 2048 |
Window size | 1800 |
Conversion to decibels | TRUE / FALSE |
Window type | eCM_HannWindow |
Scaling type | eCM_PeakAmplitude / eCM_RMS |
Requirements
Development environment | Target platform | PLC libraries to include |
|---|---|---|
TwinCAT v3.1.4018 | PC or CX (x86, x64) | Tc3_CM, Tc3_CM_Base, Tc3_MultiArray |