Ask the Experts Electrical Earthing Blog

26/09/2019 By Ian Leave a Comment

Earth Testing Procedures in Urban Environments

Electrical earth testing can be a real challenge in built-up areas. Not only are there very few soft areas to deploy the test probes, but underground cabling and conductive structures are everywhere. These two factors massively affect the measured readings leading to measured values that bear no relation to the actual electrode tested. Therefore, what follows is the Earth Testing Procedure Greymatters adopts.

Step 1

Follow the guidance in HSG47. The city or town’s infrastructure produces large amounts of in-ground noise and interference. Mitigation by reading buried service/cable records; observing signs of previous excavations; and use a cable avoidance tool (CAT) can make sense of where the structures are.

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09/08/2019 By Ian Leave a Comment

Earthing System Design Procedure A Probabilistic Approach

What are the procedures for creating an HV Earthing System Design? Also, how might these differ from an LV Earth design?

Firstly, although the principles underpinning HV and LV earthing are similar, the approaches are very different.

Probabilistic Approach

The first huge difference is the recognition that HV electrical earthing design is probabilistic in nature. Whereas LV earthing is far less so.

What do I mean?

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31/07/2019 By Ian Leave a Comment

What is an Earthing System – A Definitive Guide to Earthing, Grounding Systems

In Electrical Engineering terms, earth or, grounding system is the point of reference in an electrical circuit from which the voltages are estimated. The earthing system or to our friends over the pond; grounding system also has the function of providing a common return path for electric current through a physical connection to the geology. In an electrical installation, an earthing system or grounding system electrode connects specific parts of that installation with the Earth’s conductive surface for safety and functional purposes.

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28/06/2019 By Ian Leave a Comment

Low Voltage & High Voltage Earthing Protection – A Case Study at an EFW Plant

In the context of electrical earthing or grounding. Earthing Protection defined as the Protective Earthing of electrical installations at low voltage, i.e. <1,000V AC as described in Electrical Earthing Standards BS 7430.

So, in this case, study. We take a look at a few challenges we came across while designing the HV Earthing and Lightning Protection Systems. For a 9MW Energy from Waste Plant in Europe.

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19/06/2019 By Ian Leave a Comment

Are you getting tired of people stealing your lovely earthing arrangements

Good news – having just finished a project to pin lovely shiny copper conductors to their supporting structures protecting their Earthing Arrangements. We’ve ended up with quite a few surpluses of the Fischer FNAII stainless pins (we call them Titan pins – part no. 044112) leftover … 3,400 to be exact!

These bad boys are simple to fit concrete structures using a 6mm dia masonry drill at discrete spacings (typically 500mm) to make things incredibly hard for a thief to remove the valuable conductor without spending considerable time trying. This Anti-theft earthing arrangement is not a silver bullet, but even if they do persist all that they can practically do is to cut away a 500mm section at a time not 10’s or 100’s of meters — therefore slowing the whole process down massively.

Thus, making things incredibly frustrating for the thief and making them more vulnerable to getting caught as well as reducing how much of the conductor goes missing.

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Ask the Experts Electrical Earthing Blog

Step 1

Probabilistic Approach

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