Earth resistance is a measure of the opposition to the flow of electric current through the earth. It is a critical parameter in electrical grounding systems as it ensures the safety of people and equipment by providing a low resistance path for electrical faults.
Earth Resistance is typically measured using a device called an Earth Resistance Tester, also known as a Ground Resistance Tester. This instrument applies a known voltage to the ground and measures the resulting current to calculate the resistance.
The standard value for Earth Resistance varies depending on the type of electrical system and the local regulations. However, a commonly accepted standard value for Earth Resistance in a commercial or industrial setting is 25 ohms or less.
Earth Resistance is important for ensuring the safety of people and equipment in electrical systems. It helps to prevent electrical shocks and damage caused by electrical faults. It also ensures the proper functioning of sensitive electronic equipment by providing a stable reference point for electrical signals.
Several factors can affect Earth Resistance, including soil type, moisture content, temperature, and the presence of other conductive materials in the ground. Improper installation or damage to grounding systems can also impact Earth Resistance values.