What are the working principles of earth tester megger?

1. What are the working principles of Earth Tester Megger? The Earth Tester Megger is a direct reading ohmmeter that comes with a hand-driven generator supplying the testing current flow. The ohmmeter consists of two coils - a current coil and a pressure coil with four terminals fixed on a common axis. The earth resistance limits range from less than 1 ohm for power stations to less than 5 ohms for the sub-stations. The user needs to be careful that resistance should be as small as possible for two reasons: During a fault on a metal frame coming in contact with the live wire, a current will flow through the earth's connection, leading to a probable distinction between the metal frame and the earth, which is relative and should be sparse. This is because it will function across an individual who connects with the metal frame when in a fault condition. Low resistance to the earth lets a high current flow during a fault. Due to the high current, the fuse will melt in a short time, thus disconnecting to faulty machine from the lines, thus assuring safety. Why do we need to have Earthing and Earth Resistance? Earthing for an electrical installation is essential due to many reasons. Some of them are: Electrical equipment & their parts must be linked to an earth electrode. It protects the various parts of the installation and the persons working against damage if the system's insulation fails.

2. Connecting these parts to an earthed electrode allows a continuous low-resistance path for leakage currents to flow to the earth. This current operates the protective devices; thus, the faulty circuit is isolated if a fault occurs. During the overvoltage, the earth electrode ensures that the dead equipment parts do not get dangerously high possibilities. It can happen due to lightning discharges or other system faults. In a three-phase circuit, the system's neutral is earthed to stabilize the potential of the circuit concerning the earth. An earth electrode will only be effective when it has a lower resistance to the earth and holds considerable currents without deteriorating. Since the amount of current an earth electrode will carry is difficult to measure, the earth's resistance value is a reliable indicator of its effectiveness. The resistance of the earth electrode should be to give good protection, and it must be measured. The resistance of any earthing system depends are: The exact resistance of soil and in the area around electrodes. Form and material of earth electrode of electrodes utilized. Deepness in the soil at which the electrodes are placed. The precise soil resistance is not consistent and depends on different soils. The moisture content in the soil affects its specific resistance of earth electrodes is not a consistent factor but suffers seasonal variations. This calls for routine testing so that the earthing system remains well effective. A high-quality Earth Tester Megger can check the earth's resistance well. You can grab them from an authentic Dealer of Megger. CONTACT US: OMNI CONTROLS INC.: https://www.omnicontrols.com/ Commerce Park Professional Center 5309 Technology Dr. Tampa, FL 33647 P: 813.971.5001 Email: sales@omnicontrols.com