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Why do I need an Earthing Study?

Why do I need an Earthing Study?

Saving lives in earthing design

GreyMatters exists to protect critical assets and life, from the harmful effects of High Voltage and Lightning globally.

If we save just one life as a result of what we do…we will have succeeded.

What is an Earthing Study?

An earthing study is a type of engineering analysis that is used to determine the design and safety of the grounding system for a particular facility. There are several reasons why an earthing study may be necessary:

  1. Safety: A properly designed grounding system is essential for ensuring the safety of personnel and equipment. It helps to protect against electric shock and fires, and it can help to prevent damage to electronic equipment.
  2. Compliance: Many countries have regulations and standards that require facilities to have a grounding system that meets certain specifications. An earthing study can help to ensure that a facility’s grounding system meets these requirements.
  3. Performance: A grounding system that is not properly designed or maintained can cause problems with the performance of electronic equipment, such as interference with communication systems or damage to sensitive electronic components. An earthing study can help to identify and address these issues.
  4. Warranty: Some manufacturers of electronic equipment may require that a facility have a properly designed and maintained grounding system in order to maintain the equipment’s warranty. An earthing study can help to ensure that a facility meets these requirements.

Fault Theory

To better understand why you need an earthing study, it’s important to know the fundamentals behind earth fault theory. Let’s take a quick look at a high fault in progress, the impact locally and to the wider community.

That was a visual representation about fault theory. On the HV side we have the fault or unplanned release of energy and on the other humans or livestock. Obviously, these two don’t mix particularly well unless we can keep the energy levels BELOW what the heart can tolerate.

Enter Charles Dalziel!

Charles Dalzal

Charles devoted his time studying how the human body responds to electrocution. Understandably there were not many volunteers for the task, so he spent a good deal of time electrocuting himself to study the impacts of electricity and high voltage on the body. So, we owe a great debt to his work.

The results from his experiments formed the basis of IEC 60479-1 ‘Effects of current on human beings and livestock’.

And in simple terms, this is what drives whether you need an earthing study or not. The standards state you need to show that the impact of a sudden/unplanned release of energy to anyone nearby won’t come to harm.

Knowing what we know about the human tolerance during a fault condition you must therefore demonstrate you have taken all reasonable steps to avoid putting people and livestock at risk of harm.

By calculating what the surface voltages are going to be, we can then control and manage these voltages to keep them below ventricular fibrillation.

surface voltage calculations

How do you complete an Earthing Study?

GreyMatters Earthing Design Services as professionally designed to ensure the safety of personnel and equipment in and around the project.

Earthing design process
Flowchart demonstrating the earthing design process

Using the latest Finite Element Analysis software simulation tools, such as XGSlab and CDEGS can do the heavy lifting for you. They will turn the complex…into an easy-to-understand visual map or plan showing you where the electrical risks are.

Therefore, using the latest top 1% software our studies include:

  • Fault current distribution (or split)
  • Earth potential rise (EPR)
  • Safety voltages (Touch and step)
Earthing study report
Example output of a typical earthing report study​

Find out how the latest integration tools within XGSLab can make your Earthing reports really pop and ‘Bring Your Design to Life’ in a visually and geometrically accurate way – watch the webinar replay here.

Example Project

Solar farm in North Wales:

  • With water pipes running nearby, including one through the site
  • Combination of Asbestos cement and case iron.
key data
Key Data
Model layouts

What conclusions we can draw?

  • There’s a very high potential on the pipe within the PV array, but this reduces quickly
  • Beyond the site, the risk to people working on the water pipes is low – the voltage on the pipe is of the order of a few hundred volts, and we have fairly modern protection – so our touch voltage limit for people wearing shoes is 578 V
  • So, if personnel are working on a pipe within the PV array itself, we need to consider measures to protect them
  • But beyond the array, measures are less likely to be required.
  • Sensible to consider providing isolation to pipes at boundary of hot zone

Engage with us…

  • Earthing Design Services & Lightning Protection Design – If high voltage power systems and lightning are causing you concern why not see how we can help with a quick ‘live chat’ below as a start.
  • XGSLab – A complete software tool for the simulation of  Power, Earthing, Grounding and Lightning Systems, get in touch to request a free demo.
  • Get Certified – Start your journey to become certified in Power Systems Earthing & Design.

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