James Wren is an Application Engineer and the Sales Manager for Prosig Limited. James graduated from Portsmouth University in 2001, with a Masters degree in Electronic Engineering. He is a Chartered Engineer and a registered Eur Ing. He has been involved with motorsport from a very early age with special interest in data acquisition. James is a founder member of the Dalmeny Racing team.

James Wren is an Application Engineer and the Sales Manager for Prosig Limited. James graduated from Portsmouth University in 2001, with a Masters degree in Electronic Engineering. He is a Chartered Engineer and a registered Eur Ing. He has been involved with motorsport from a very early age with special interest in data acquisition. James is a founder member of the Dalmeny Racing team.

## Example of performing a Moving Average

This tutorial guides a DATS user through the steps required to perform a moving average on a given signal. The tutorial explains the concept of the ‘Integration Length’ and the ‘Output Interval Step’.

Initially a signal is required to perform the moving average on. In this tutorial a sine wave will be generated. A sine wave is generated using the parameters shown in Figure 1.

## Is it possible to connect the BNC outer to ground when using a P8000?

A question was recently posed regarding the grounding conditions of a BNC type input. The shield or outer of a BNC cable or connector is not connected to the chassis or ground. What would happen if it was connected to ground?

## What is the maximum analysis frequency for a waterfall in DATS?

The maximum analysis frequency is always half the sample rate of the input signal.

So if your data is captured at 50kHz the maximum analysis frequency will be 25kHz.

## Creating Order Plots Using The DATS Rotating Machinery Software

In this tutorial we will be creating order plots using waterfall and intensity displays using use the DATS.toolbox and Rotating Machinery Analysis option.

To begin, a noise, vibration or other signal of interest should be captured along with a tachometer signal.

In Figure 1 we have loaded a time series (in this case an acceleration signal) and a time series of a tachometer pulse train into the DATS software.

## How to use an Analogue Channel with Tachometer Signals on the P8000

When using an analogue channel input channel of a P8000, with a tachometer sensor, is it possible to utilise the tachometer processing functions as you would if you were using a tachometer input of the P8000?

For example could you display an RPM on an analogue channel?

When using an analogue channel it is possible to select, from the signal setup matrix, ‘Trigger Type’, with this option set to ‘Tacho’ and the ‘Trigger Level’ set to the voltage crossing threshold several features become available in terms of tachometer processing.

By selecting the above options the user will be able to use the ‘Digital Panel’ display type from the signal display and thus by selecting the ‘Speed’ option in the ‘Display Type’ drop down list an RPM will be available.

## What is waterfall frequency spacing? And how does the DATS parameter ‘Requested Frequency Spacing’ work?

Let us try to understand what waterfall frequency spacing is. Waterfall frequency spacing is the gap between spectral lines in an FFT plot.

For example, if you had an analysis frequency of 0Hz to 100Hz and 100 spectral lines, then Frequency Spacing is 1Hz.

So why is there a ‘Requested Frequency Spacing’ and an ‘Actual Frequency Spacing’? Continue reading What is waterfall frequency spacing? And how does the DATS parameter ‘Requested Frequency Spacing’ work?