James Wren

Author's details

Name: James Wren
Date registered: September 1, 2011
URL: http://www.linkedin.com/profile/view?id=70047234

Biography

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 member of the Institution of Engineering and Technology. 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.

Latest posts

  1. Sound Mapping Software Example — September 17, 2014
  2. What is waterfall frequency spacing? And how does the DATS parameter ‘Requested Frequency Spacing’ work? — August 28, 2014
  3. What is “waterfall smearing”? — August 20, 2014
  4. Multiplane Balancing – Zero Imbalance or Specified Imbalance — July 28, 2014
  5. Is it important to consider the cable resistance when using strain gauges? — June 24, 2014

Most commented posts

  1. What engineering decisions are made by measuring a power spectrum? — 2 comments
  2. How To Choose A Sample Rate For A Required Analysis Frequency Range — 2 comments

Author's posts listings

Sep 17

Sound Mapping Software Example

Here is a short example using the DATS Sound Mapping software to identify the source of noise from a 4-cylinder car engine.

Aug 28

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 …

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Aug 20

What is “waterfall smearing”?

Waterfall created using a suitable frequency resolution

When analysing a waterfall or performing order analysis it is important to consider the frequency resolution or the frequency spacing. There is often a desire to increase the resolution to finer and finer detail. But that is a process of diminishing returns, and actually fraught with danger. And that danger is waterfall smearing.

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Jul 28

Multiplane Balancing – Zero Imbalance or Specified Imbalance

In the DATS Multiplane Balancing Software, there are two options, optimise for ‘Zero imbalance’ or optimise for ‘Specified imbalance’, but what is the objective of these two options?

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Jun 24

Is it important to consider the cable resistance when using strain gauges?

The cable resistance can be a significant factor in the accuracy of the overall measurement. It is very important indeed to consider this point. Prosig software allows the cable resistance to be entered by the user. Once this resistance has been entered, any calculations or calibrations carried out will be based on the known values …

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Jun 19

How should the bridge factor be selected when using strain gauges?

The number of active arms in a strain gauge Wheatstone bridge is known as the bridge factor. As a simple guide when selecting bridge factors the following rules apply;

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Jun 16

When should I use the ground connection on my P8000 data acquisition system?

The ground connection should be used if an issue has been observed in measured data, such as significant electricity supply (50Hz or 60Hz) distortion or significant noise. It must be attached it to a very good earth point (like a steel pipe or foundation) It should be noted that sometimes connecting the ground cable to earth …

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May 13

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.

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May 09

What Is A Load Spectrum?

When engineers talk about the ‘Load Spectrum’ what do they mean? There is no simple answer, simple terms like load and spectrum can be used in different situations and therefore to mean different things. However the most common definition of load spectrum is as follows…

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May 06

How Do I Convert To Decibels?

Much confusion revolves around linear and non-linear numbers. The following outlines the mathematical process to convert from a number expressed in dB to a linear quantity. How do we convert to decibels and back again?

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