Earthing Tests

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Earthing Tests

When it comes to safety, grounding, or earthing, tests are the hallmark of electrical safety around the world. While simple, these tests determine the overall safety of an electrical installation and confirm that the installation can run smoothly without adding the risk of electrical shocks, electrical failures, or even fires.

Earthing tests are part of general electrical inspections and testing procedures. These tests are required to be conducted on any new or old installation. Many people believe that electrical installations are sacred – once you have installed them, you don’t need to revisit them.

This, however, is far from the truth! While properly installed electrical installations can stand the test of time, they aren’t permanent! In fact, even in the case of high-quality installations, these systems still require timely maintenance checks due to depreciation and deterioration of wires and electrical components.

For example, over time, electric installations can wear down and cause a lot of problems that can result in sparks, shocks, inefficiencies, and even fires.

Inadequate or worn-down earthing systems, which play a key role in preventing electrical shocks or other such high-voltage events, can particularly cause a lot of problems like fires, damage to appliances and components, along with severe electric shocks.

In this guide, we will look at the importance of earthing, the purpose of earthing tests, and how to ensure the safety of electrical installations using scheduled maintenance checks and safety best practices.

Read below to find out more:


You might not realise but the earth is a conductive ball that is capable of not just holding but also dispersing current. However, since the earth is made of different conductive parts like water, rock, minerals, and soil, the conductivity can vary significantly.

This concept is important to know because it will help us understand the basics of grounding or earthing!

Take a look at any circuit board and you will likely find three holes. These holes not only provide a hooking point for plugs to stay in place, but they also serve different purposes.

A socket can be made up of the following parts:

  • Live
  • Neutral
  • Ground

The live wire is what carries a current from the source to a load (i.e., a light bulb or any appliance). The neutral wire provides a return path for the current so that it goes back to the source, thereby completing the circuit.

The ground wire acts as a safety component in the circuit. This wire is hardly ever used, and that is great! Ground wires are put in place to prevent damage, short circuits, shocks, and other electric-related faults.

If you trace the ground wire from a socket, you will find that instead of the wire leading to the main board, it tracks to the outside of the house.

As a simple experiment, we recommend that you take a quick look at the outside of your home, around the garden area preferably, and look for enclosed caps on the ground. These caps cover grounding points that are conveniently placed around the home to provide ample earthing for your electrical installation.

A ground point is simply a copper plate that is placed a few feet under the ground. A copper wire is ideally used to connect to this plate and the wire leads back to the inside of the house to the main grounding unit that distributes the connection across all sockets in the house.

This way, if there is excessive load in the system, the current can safely travel through the earthing wires and dissipate in the ground, thereby bypassing any electrical components in your home. This is especially important during high-voltage events or even weather disasters.

For example, lighting rods are part of the grounding system. These rods are made of copper and are placed on the roof of the house. The rod leads straight down to the ground and is a means of dissipating lightning if it were to strike the roof of the house.

Without a lightning rod or an effective earthing system in your home, the excess electricity caused by the lightning strike may jump into electric components causing severe damage, risk of shocks, and fire.

In some severe cases, the electricity may even jump to other conductive parts of your home, like plumbing made of metal or the chassis of metal appliances!


As explained above, earthing systems ensure the safety of electrical installations and are put in place to eliminate the risk of electric shocks caused by excessive electricity in the system.

An earthing test is conducted by a professional and certified electrician to make sure that the various earthing points located around the property are working as intended and that the connections to these points are not hindered by damaged wires, cuts, or water ingress.

Here is what is involved in a typical earthing test:


This stage is important because it helps electricians visually diagnose the problem in an installation. For example, if they notice that some appliances are generating a buzzing sensation or causing a small electric shock, then this would help indicate that there might be something wrong with the grounding system.

A certified electrician will use protective gear to shield themselves from rogue currents and to help them do their job more freely.

Before beginning, an electrician will look at any valid documents like an Electric Installation Certificate (EIC) or a previous Electric Installation Condition Report (EICR) to get all the information they need about the electrical installation.

Testing Process

After the electrician has all the details about the installation, they will proceed with preliminary tests that lead to the actual earthing test.

A certified electrician will use a ground resistance tester, a ground continuity tester, and a ground fault locator. In some cases, these functions may be clubbed into one device that can display the results digitally.

First, an electrician will conduct a continuity test. This test ensures that all the grounding conductors and connectors have low resistance and are free from faults.

Then, the electrician will conduct a ground resistance test. This test measures the resistance of the grounding system to electricity. Typically, the electrician will inject a known amount of current into the ground to measure the resulting drop and figure out the resistance.

The electrician will then check for voltage measurements by hooking the grounding tester to the grounding points located around the property. This test is crucial because it can help highlight inadequate grounding, grounding faults, and grounding connection faults.


Once the testing is complete, the details of the test along with the test results are documented and shared with the property owner. If the test reveals that there are faults, then the electrician will encourage you to get the problems addressed as soon as possible.

These tests are incredibly important in maintaining not just the safety of the installation but also the safety of people living on the property. We highly recommend that you talk with a certified electrician to understand more about grounding tests for your property and how you can make your electrical installation safer.


Earthing or other major (or even minor) issues in electrical installations may not immediately show up, which is why regular maintenance checks are recommended so that these potential issues don’t end up actually damaging components or worse, causing electric shocks or a fire.

Here are some telltale signs that indicate that an electrical installation requires maintenance:

Excessive Breaker Tripping

Breakers are meant to trip in the event of an electric overload. However, when they trip frequently and without any signs of excessive load, then this would indicate that the installation needs to be checked.

In some cases, a faulty earthing system can also cause excessive breaks since instead of the earthing system rerouting the excess current to the ground, the current circulates within the installation and wreaks havoc!

Flickering or buzzing lights.

Flickering or dimming of lights is a classic telltale sign of a struggling electric installation. Flickering can occur due to several reasons; however, the most common reason is a faulty connection or damage to the wire.

In some cases, flickering and buzzing can also be caused by a faulty earthing system that doesn’t dissipate current properly from appliances.

Minor Electric Shocks

You would be surprised by just how many times minor shocks are let go as “one-offs”. When minor electric shocks occur, most people assume that it won’t happen again. However, the more pressing concern is the reason behind the shock. Properly installed electric systems will never cause any type of shock. So, if you experience something out of the ordinary, always get it checked.

If the outside of appliances is causing minor shocks or if you can feel a buzzing sensation, then this would indicate that there is something wrong with the earthing system of your property.

Discolouration and smoke

Any type of discolouration is grounds for concern, especially if the discolouration is black which would indicate damage from heat or fire.

Fading colours on wires may indicate that they need replacing but they shouldn’t be a pressing matter since colour can fade with time, but if you notice a dark or brown discolouration, especially in some parts of a wire, then this would indicate that the entire system needs to be checked.

This type of damage usually occurs with excessive current and heat in the wires. While this might be caused by a faulty earthing system, it is best that you consult with a professional electrician to get to the bottom of the problem.

Odours and Burning

If you smell smoke, always call in the professionals. Odd odours, such as burning near the sockets, are a clear sign that a fire has started. Fires can be caused by a range of different issues, including faulty earthing.

You should always call emergency services during a fire, and a professional electrician later on, to thoroughly figure out the cause of the fire.


The good news is that earthing tests rarely require frequent repairs. Grounding systems are made from high-quality copper that is far more resistant to wear and tear than other sensitive electrical components.

This is why earthing systems only require monitoring and in the event of a repair, these systems can be repaired quickly compared to other complex electrical components.

If you hire a professional electrical installation company, earthing tests will be included in the maintenance schedule of your installation.

The best way to ensure that the earthing system and wiring on your property keep working as they should and stay in good condition is to have a reliable electrical contractor regularly check it out.

A professional electrician, like the ones from Calder Electrical, will be able to identify any potential or developing problems and fix them before they become an issue.

This practice will keep your home and business safe, save you money on huge repair costs, and generally put your mind at ease.

Domestic electrical inspection & testing

Wiring regulations BS 7671 state that a domestic property must be regularly inspected and tested for earthing and other electrical components after an electrical installation every 5-10 years. This testing can also be done earlier or on an ad hoc basis.

Commercial electrical inspection & testing

Under the Electricity at Work Act 1989, a business or commercial space must ensure that the electrical installation is deemed safe for use.

This can be done using an Electrical Installation Condition Report (EICR) which outlines tests at regular intervals. This report contains detailed information about earthing tests along with various other tests that ensure the safety of the installation.

Landlord Electrical Inspection & Testing

A landlord’s Safety Certificate, which involves preparing an electrical installation condition report to identify any issues in the earthing system or the installation in general, must be carried out every 5 years or whenever there is a change in occupancy.


We have been providing electrical services to residential, commercial, and industrial properties for over 40 years and are specialists in all aspects of electrical installations, maintenance, and testing.

All our work is fully insured, and we work to meet the standards set by the NICEIC to make sure all your electrical installations meet the current regulations, and all the notifiable work is signed off by the local authorities.

If you have unplanned issues within your home or business, we can provide a call-out service to rectify and solve any problems such as circuit tripping, loss of power, broken items that need repairing, or to check if you feel something is unsafe or a potential hazard.

Our team can generate a Visual Inspection Report (VIR) to identify anything visual that does not comply with the standards or looks unsafe, as well as a full Electrical Installation Condition Report (EICR) where we will identify and test each circuit to make sure they are not deteriorating and are safe for use within the current standards and regulations set by the BS 7671.

We can also provide PAT testing of appliances to make sure that any items such as kettles, computers, and microwaves are safe for use in the home and workplace.

Contact us here or call us at 0800 612 3001 to get in touch with our professional electricians for more information on earthing tests and the importance of regular electrical maintenance and testing for your property.

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