CDEGS - Avoid being caught-out with The Wrong Trousers

CDEGS Certified User - The Right Trousers

CDEGS Misconception

The term ‘CDEGS’ is loosely banded around a lot in our sector to deliver safe Electrical Earthing System Design when carrying out earth potential rise studies.  The trouble is there’s a lot of confusion and misinformation surrounding which version of CDEGS should be used for what application.

Generally, the misconception is that there’s only one CDEGS … wrong!

There are a number of versions of CDEGS in the market place and each with a bewildering number of ‘engineering modules’.  We’ve covered the different choices available in a previous post [CDEGS myths busted]. In this piece I’d like to share some misconceptions and highlight what you can do to avoid having the wrong version used on your project.

But why should this matter?

Simple …

Select the wrong version of CDEGS for your project and what you ‘thought’ to be a sound / safe design could be completely out of whack.  When the wrong version is inadvertently used, it is not unusual to see an error rates climb into the many 100’s of percent for Earth Potential Rise (EPR). As a consequence, the safety step and touch voltages are thrown into chaos.

Bottom-line, Earthing is a safety-critical part of the overall electrical design… Without understating the obvious, get this wrong and people can die!

Protecting Life

The whole reason why GreyMatters exists is to protect life. - So making sure you get the correct version and accurate safety scenario deeply matters to us!  However, getting the correct version for your project should be a relatively easy thing to sort out. What is more challenging is ensuring the user(s) have the appropriate level of formal underpinning competency to ‘drive’ the software itself. - A CDEGS Certified User.

In today’s increasingly litigious world, getting caught driving a car you own without a valid driver’s license will result in a hefty fine and a possible time spent behind bars.  This analogy broadly applies to Engineering Design. - It’s not enough to own a tool, or a piece of software, or machinery… The user (the driver if you will) must also be able to demonstrate formally his/her competence before being allowed behind the wheel.

Qualified Drivers

CDEGS is no different in this respect.  Owning a licensed version of CDEGS is only half the story… Having a qualified driver to ‘drive’ the software is the other half.  Here are some interesting facts taken from the developers SES:

At the time of writing, there are 814 companies worldwide listed with some form or version of CDEGS. There are only 211 individuals worldwide (15 in the EU) that are CDEGS Certified User(s) formally qualified to ‘drive’ this software.

Out of the CDEGS Certified Users in the UK - GreyMatters accounts for one third (33%) of the total UK CDEGS Certified User head-count.

CDEGS Certified User StatsCDEGS Certified User StatsCDEGS Certified User Stats


Image credit: Aardman Animations

Caught with the Wrong Trousers

Similarly, as in the Aardman film featuring Wallace and Gromit 'The Wrong Trousers'.  Wallace gets himself caught up in some pretty unforeseen scrapes when his robotic trousers are controlled by a penguin called Feathers McGraw.  With this in mind. I felt compelled to write this piece so that YOU aren’t caught with YOUR trousers down so to speak.

Your assumptions are your windows on the world. Scrub them off every once in a while, or the light won't come in.  - Isaac Asimov.

Check Now

Have you checked your assumptions recently?  If CDEGS is being used on your Earthing Study or Earth Potential Rise calculations for your earthing design. Then check and confirm the driver is a CDEGS Certified User.

If in doubt, visit the CDEGS certified user pages. Or ask us here at GreyMatters, where representing 33% of the UK's CDEGS Certified User base, competency is assured.

Ian Griffiths SelfieIan Griffiths

This post is written by Ian Griffiths, Principal Engineer at GreyMatters, an Earthing Consultant of 26 years, one of the top 1% accredited CDEGS consultants and professional advisor to international utility companies, data-centre and infrastructure developers.

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"Working with GreyMatters has totally changed my expectations of a professional engineering consultancy firm … for the better! Technically, they were on the money! More importantly however ... they kept me updated throughout the entire project, which was so refreshing, and therefore quickly put my mind at ease that things were being taken care of." (C. Turgis)
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