Grounding allows leakage currents to flow without creating hazards. When combined with an automatic breaking device (differential circuit breaker), it switches off the electrical installation. The metal body must be grounded from any touching element, which is normally isolated from the electrical current but in contact with the current.
This applies to a wide variety of appliances, including water heater, stove, washing machine, refrigerator, motor, lamppost, fluorescent tube, metal frame of a door and more.
A washing machine that is not plugged into a grounded outlet in a tiled laundry room can compromise safety. If a mouse strips the power cable of the machine and the electrical wires come into contact with the machine, and a user touches the machine. Since the user is on a conducting ground they are are exposed to the electric current.
Grounding Products Online associated with the differential circuit breaker prevents incident. The current goes directly into the ground and the power is automatically cut off. No more electrocution, no more danger.
Equipment of an electrical installation (sockets and outlets) and protective conductors (yellow and green cables) play a key a role in the installation. Another vital aspect is the main equipotential bonding of the buildings, which include the conductive elements like a metal frame, the metal pipes of gas, water or heating. The same applies to the equipotential links of the water rooms.
Grounding is effective if it is associated with a differential device. It consists of a good conductive metal electrode that is non-corroding and in good contact with the ground.
The electrode can be of different types with the applicable minimum dimensions: One or more stakes sunk vertically below the permanent moisture level to a minimum depth of 2 meters. Either 25 millimeters diameter galvanized steel pipe, or 60 millimters galvanized mild steel pipe or copper or copper-plated steel 15 millimeters in diameter.
In addition, it should feature one 25 millimeters bare copper or 95 millimeters galvanized steel buried cable. A steel strip of 100 mm and 3 mm thickness or a 95 mm cable, embedded in the foundation concrete.
A good grounding must have an electrical resistance determined according to the sensitivity of the differential device of the installation of the house. With a circuit breaker and selective differential connection (type S) of 500 mA, the maximum resistance of the earth electrode must be 100 ohms.
This resistance depends on the dimensions of the earth electrode, its shape and the resistivity of the ground, knowing that this resistivity varies according to the depth, the moisture content and the temperature.
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