Search results
Results from the WOW.Com Content Network
The primary reason for the use of isolated grounds (IG) is to provide a noise-free ground return, separate from the equipment grounding (EG) return. The EG circuit includes all of the metal conduit, outlet boxes, and metal enclosures that contain the wiring and must be grounded to provide a safe return path in case of fault currents.
Sometimes the fittings are considered sufficiently conductive to bond (electrically unite) the metal conduit to a metal junction box (thus sharing the box's ground connection); other times, grounding bushings are used which have bonding jumpers from the bushing to a grounding screw on the box.
While the national wiring regulations for buildings of many countries follow the IEC 60364 terminology, in North America (United States and Canada), the term "equipment grounding conductor" refers to equipment grounds and ground wires on branch circuits, and "grounding electrode conductor" is used for conductors bonding an earth/ground rod ...
A semi-conducting glaze may be used to assist in equalizing the electrical potential gradient along the length of the bushing. The inside of the porcelain bushing is often filled with oil to provide additional insulation and bushings of this construction are widely used up to 36 kV where higher partial discharges are permitted.
Long-distance electromagnetic telegraph systems from 1820 onwards [a] used two or more wires to carry the signal and return currents. It was discovered by German scientist C.A. von Steinheil in 1836–1837, that the ground could be used as the return path to complete the circuit, making the return wire unnecessary. [2]
A ground connection that is missing or of inadequate capacity may not provide the protective functions as intended during a fault in the connected equipment. Extra connections between ground and circuit neutral may result in circulating current in the ground path, stray current introduced in the earth or in a structure, and stray voltage.
A halo ground is a type of ring ground that, instead of being installed outside and underground, is installed inside, near the top of a building or structure. The ...
Bushing (bearing), a type of plain bearing; Bushing (electrical), an insulated device that allows a conductor to pass through a grounded conducting barrier; Bushing (isolator), a mechanical device used to reduce vibrational energy transfer between two parts; Drill bushing, a tool used to guide the placement of a hole when drilling in a workpiece