Manfred Weber
Metra Mess- und Frequenztechnik in Radebeul e.K.
PC Vibration Measurement System VibroMetra

Operation mode

Operation mode

Select operation mode

1. Select operation mode
VM-FFT supports several operation modes. The following can be selected:
FFT with automatic settings according to frequency axis
The FFT parameter are set automatically. Only the required frequency range is set individually. VM-FFT takes this into account and determines the line density. The time window is set automatically so that each displayed line is verified by a calculated one. The flattop window is used for weighting in time range because it displays magnitudes especially accurate.
Since the selected frequency is a measure for the FFT parameter, the FFT is setup again when the frequency changes.
FFT with manual settings
Two additional control panels appear - Trigger and FFT. Numerous parameter for the FFT can be set manually and the FFT can be performed with a trigger if required.
Envelope analysis for bearing diagnostics
A third additional control panels appears - Bearing diagnosis. Those settings allow an easy assignment of the displayed frequencies to bearing damages.
Power spectral density
For stochastic vibration processes or the impact of vibration with the transport of goods the power spectral density analysis (PSD) is often used. With this mode a matching control panel appears.
Frequency response function
A force signal is generated by an impulse hammer. The accelerometer measures the response signal. A number of FRF modes can be selected.
Acoustics (FFT with weighting filter)
This mode performs a FFT for acoustic values. A linear, A or C weighting filter can be selected.