A short video tutorial describing how to create an orbit plot using the DATS software
Tag: vibration
What engineering decisions are made by measuring a power spectrum?
By power spectrum we are talking about an ASD (Auto Spectral Density) or PSD (Power Spectral Density). In fact PSD is often used when really ASD would be more correct.
Taking any signal and performing a frequency analysis using an ASD or a PSD will give the energy over a range of frequencies. Continue reading What engineering decisions are made by measuring a power spectrum?
What is Auto Spectral Density?
The Auto Spectral Density or Auto RMS spectrum analyses uses Fourier Transforms to process optionally overlapped sections of the input data. The result of each Fourier analysed section is called a periodogram. We then process all the resulting periodograms to produce a spectral result. Continue reading What is Auto Spectral Density?
[Video] Exporting DATS datasets in non-linear format
To complement our recent post on Exporting DATS datasets in non-linear format here is James Wren demonstrating the method.
What Sample Rate Do I Use To Measure Whole Body Vibration?
What sample rate should I use if I am measuring whole body vibration?
Strict ISO8041 compliance imposes a minimum sample rate of 900 samples per second. This ensures the amplitude and phase characteristics of the applied weightings meet the required criteria. To take account of the anti alias hardware filter we would recommend 1200 samples/second. If non-strict compliance is used the minimum sample rate is 300 samples/second.
ISO2631-1 recommends a minimum data duration of 227 seconds. However, for greater reliability, 600 seconds is now considered essential. That is, a 600 second or longer signal will be more representative and will provide better quality results.
How to set up scheduled data captures
A video that explains how to set up the DATS Data Acquisition software to perform captures at specific, scheduled times.
[Video] Create AVI files from your structural animations
The DATS Modal Analysis software consists of Hammer Impact Testing, Modal Analysis & Structural Animation (often referred to as Operational Deflection Shapes or ODS and Running Modes). Having measured and analysed your data the Structural Animation software allows you to visualisation your structure under certain operating conditions. These visualisations can then be saved as AVI files. This video shows you how…
Relative signal levels of a sinusoid with and without background noise
In the process of looking at some order data, a question about the accuracy of the measurement of the signal level of discrete frequency signals which were close to the general noise level. To answer this question, a small DATS worksheet was created which generated 2 signals. The first signal was a 35 Hz sinusoid which, by itself the spectrum level was measured to be approximately -9 dB (ref 1 V) as seen in Figure 1.
Continue reading Relative signal levels of a sinusoid with and without background noise
[Video] Creating speed signals for data with no tacho
So you’ve got some noise and/or vibration data from a rotating machine, but no speed information. Surely that means you can’t analyse against speed or do any order analysis, right? Well, not quite!
The DATS Rotating Machinery option now comes with a tool to create speed v time data using your noise or vibration signals.
Watch the video to find out how…
[Video] Using reference cursors to measure data
A tutorial by James Wren (Prosig UK) on how to use the reference cursors in the DATS software to precisely measure features in your data.