How to test earthing electrode resistance?

The resistance of the earthing electrode can be measured through different methods. The testing depends on the type of neutral system, installation type, and the likelihood of power supply termination. Four variables impact the resistance of an earthing system. These are: 1. Soil composition 2. Soil's moisture content 3. Soil temperature 4. The depth of the electrode The resistance of earthing electrode is contingent on the soil's resistivity. Thus, it becomes imperative to measure the resistivity of the soil where the electrode is to be inserted. Several test methods are used to measure earthing electrode resistance. The tests are based on a site's fall of potential (FOP). Considering these factors, the following most commonly employed methods are used for measuring earthing electrode: - Fall of Potential 61.8 percent test - Fall of Potential - Test using a clamp on CT - Fall of Potential - Slope test In the FOP method, two auxiliary earth electrodes apart from the test electrode are placed at ideal distances from the test electrode. A controlled current is passed between the auxiliary current electrodes and the test electrode. Through this method, the potential difference between the auxiliary current electrode and the test electrode is measured.

Which electrode is used for earthing purposes?

Galvanized iron or GI electrode is most commonly used for the earthing system. The GI earthing electrodes boast high resistance to corrosion and a good current dissipation rate. It also doesn't require periodical moisturizing or pouring of water. Besides, GI earthing electrodes are cost-effective in comparison to others.

What are the types of earthing electrodes?

There mainly four types of earthing electrodes, namely: - Pipe earthing - Plate earthing - Rod earthing - Mat earthing Out of these earthing electrode types, the pipe earthing electrode is the most commonly used as it is suitable for all types of soil.

What is the difference between GI Earthing Electrode and Earthing Electrode Rod?

GI earthing electrode is made of galvanized iron. This can be manufactured as pipes, rods, or plates while earthing electrode rod is manufactured in the shape of a solid rod with a pointed tip for smooth penetration into the earth's surface.

How do you manufacture an earthing electrode?

Earthing electrodes can be manufactured using different materials, such as copper, stainless steel, galvanized iron (GI), etc. The electrodes are manufactured as rods, plates, pipes, or mats. Depending on the type of earthing electrode, engineers adopt the manufacturing technique. For instance, GI earthing electrode is made by coating iron with a certain percentage of zinc. Likewise, a copper electrode is manufactured by molecularly bonding 99.9% pure electrolytic copper upon a low-carbon steel structure.

What is the function of an earthing electrode?

The main function of an earthing electrode is to create a safe space for human beings for protection from electrical shocks or to create a zero potential surface level around the area where electrical equipment is installed. Earthing electrodes work by preventing the occurrence of dangerous voltage and safe dissipation of fault currents through the earthing system.