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Owning Palette: Transient Analysis VIs

Installed With: Sound and Vibration Measurement Suite

Performs a short-time Fourier transform (STFT) on scaled signal [EU] and returns the power spectrum, waterfall, or colormap at the various times you specify.

Use the pull-down menu to select an instance of this VI.

Select an instance SVT STFT vs Time (Intensity)SVT STFT vs Time (Waterfall)SVT STFT vs Time (Colormap)

SVT STFT vs Time (Intensity)

	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	FFT block size specifies the number of samples used to compute one FFT.
	window is the time-domain window to be used. 0 Uniform 1 Hanning (default) 2 Hamming 3 Blackman-Harris 4 Exact Blackman 5 Blackman 6 Flat Top 7 Four Term Blackman-Harris 8 Seven Term Blackman-Harris 9 Low Sidelobe
	time segment specifies which segment of the time-domain signal to analyze. from [s] specifies the initial value for the time segment expressed in seconds. to [s] specifies the final value for the time segment expressed in seconds. time increment specifies the time increment between two consecutive FFT blocks. time increment units sets the units used to specify the time increment. The default value is percentage, with 100 percent corresponding to no overlapping.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	dB On specifies if results are expressed in decibels. The default is TRUE. The dB reference is specified when the scaling from voltage to engineering units is applied.
	weighting specifies the weighting filter of interest. Use Linear if no weighting is needed. Linear (default) A-weighting B-weighting C-weighting
	power spectra [dB EU] returns the power spectra.
	unit label returns the selected engineering units.
	f0 and delta f [Hz] contains scaling information for the frequency axes of the power spectra. f0 is the minimum value of the frequency axis expressed in hertz. delta f is the frequency resolution expressed in hertz.
	t0 and delta t [s] contains the minimum value of the time segment and the increment. t0 is the minimum value of the time segment expressed in seconds. delta t is the time increment expressed in seconds.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	spectrum info returns information about the spectrum needed by the Spectrum Extended Measurements VIs, the Waterfall Display VIs, the Distortion VIs, and the Single Tone Measurements VIs. Do not modify the spectrum info values.

SVT STFT vs Time (Waterfall)

	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	FFT block size specifies the number of samples used to compute one FFT.
	window is the time-domain window to be used. 0 Uniform 1 Hanning (default) 2 Hamming 3 Blackman-Harris 4 Exact Blackman 5 Blackman 6 Flat Top 7 Four Term Blackman-Harris 8 Seven Term Blackman-Harris 9 Low Sidelobe
	time segment specifies which segment of the time-domain signal to analyze. from [s] specifies the initial value for the time segment expressed in seconds. to [s] specifies the final value for the time segment expressed in seconds. time increment specifies the time increment between two consecutive FFT blocks. time increment units sets the units used to specify the time increment. The default value is percentage, with 100 percent corresponding to no overlapping.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	dB On specifies if results are expressed in decibels. The default is TRUE. The dB reference is specified when the scaling from voltage to engineering units is applied.
	weighting specifies the weighting filter of interest. Use Linear if no weighting is needed. Linear (default) A-weighting B-weighting C-weighting
	waterfall graph returns an array of 2D waveform signals in three dimensions. You can display this information with the Waterfall graph. z0 returns the initial value of the first plot on the z-axis. dz returns the interval between plots on the z-axis. plots returns the data on the waterfall graph. x0 returns the initial value on the x-axis. dx returns the interval between points on the waterfall graph. Y returns the values of the points on the waterfall graph.
	unit label returns the selected engineering units.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	spectrum info returns information about the spectrum needed by the Spectrum Extended Measurements VIs, the Waterfall Display VIs, the Distortion VIs, and the Single Tone Measurements VIs. Do not modify the spectrum info values.

SVT STFT vs Time (Colormap)

	scaled signal [EU] specifies the scaled signal expressed in the selected engineering units. To obtain a properly scaled signal, you can use the SVL Scale Voltage to EU VI or define a virtual channel in National Instruments Measurement & Automation Explorer (MAX). t0 is the start time of the waveform. dt is the time interval in seconds between data points in the waveform. Y contains the data values of the waveform.
	FFT block size specifies the number of samples used to compute one FFT.
	window is the time-domain window to be used. 0 Uniform 1 Hanning (default) 2 Hamming 3 Blackman-Harris 4 Exact Blackman 5 Blackman 6 Flat Top 7 Four Term Blackman-Harris 8 Seven Term Blackman-Harris 9 Low Sidelobe
	time segment specifies which segment of the time-domain signal to analyze. from [s] specifies the initial value for the time segment expressed in seconds. to [s] specifies the final value for the time segment expressed in seconds. time increment specifies the time increment between two consecutive FFT blocks. time increment units sets the units used to specify the time increment. The default value is percentage, with 100 percent corresponding to no overlapping.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	dB On specifies if results are expressed in decibels. The default is TRUE. The dB reference is specified when the scaling from voltage to engineering units is applied.
	weighting specifies the weighting filter of interest. Use Linear if no weighting is needed. Linear (default) A-weighting B-weighting C-weighting
	colormap returns the spectral results converted from the waterfall data. You can display this cluster as a Colormap to show the transient results on an intensity graph with a rainbow color scale. spectral map returns the 2D array of magnitude data converted according to the scaling parameters. X scale returns the scaling information associated with the first index of the 2D spectral map. offset returns the x value associated with elements (0, n) of spectral map. multiplier returns the x-axis spacing between consecutive elements in a column. Y scale returns the scaling information associated with the second index of the 2D spectral map. offset returns the y value associated with elements (n, 0) of spectral map. multiplier returns the y-axis spacing between consecutive elements in a row. attribute returns additional information about the spectra. LabVIEW uses this information to display the data properly and to perform extended measurements.
	unit label returns the selected engineering units.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	spectrum info returns information about the spectrum needed by the Spectrum Extended Measurements VIs, the Waterfall Display VIs, the Distortion VIs, and the Single Tone Measurements VIs. Do not modify the spectrum info values.