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Intentional electrical connection to a reference conducting plane, which may be earth, but which more generally consists of a specific array of interconnected electrical conductors referred to as the grounding conductor.


Intentional electrical connections to a reference conducting plane, which may be earth (hence the term ground), but which more generally consists of a specific array of interconnected electrical conductors, referred to as the grounding conductor. The symbol which denotes a connection to the grounding conductor is three parallel horizontal lines, each of the lower two being shorter than the one above it (Fig. 1). The electric system of an airplane or ship observes specific grounding practices with prescribed points of grounding, but no connection to earth is involved. A connection to such a reference grounding conductor which is independent of earth is denoted by use of the symbol shown in Fig. 2.

The subject of grounding may be conveniently divided into two categories: system grounding and equipment grounding. System grounding relates to a grounding connection from the electric power system conductors for the purpose of securing superior performance qualities in the electrical system. Equipment grounding relates to a grounding connection from the various electric-machine frames, equipment housings, metal raceways containing energized electrical conductors, and closely adjacent conducting structures judged to be vulnerable to contact by an energized conductor. The purpose of such equipment grounding is to avoid environmental hazards such as electric shock to area occupants, fire ignition hazard to the building or contents, and sparking or arcing between building interior metallic members which may be in loose contact with one another. The design of outdoor open-type installations presents special problems.

Installations in which earth is used as a reference ground plane present special problems. To design an earth “floor surface” for an outdoor open-type substation which will be free of dangerous electric shock voltage exposure to persons around the station is a difficult task.


i. Declaring a pilot or an aircraft unfit to fly by the competent authority.
ii. Connecting a conductor to a ground or earth circuit.
References in periodicals archive ?
the possibility of arbitrary orientation of the grounding.
For specified point such a deviation can be explained by the difference in the cross section of the local grounding, its corrosion wear, or the difficult path of the grounding trail (the depth of bedding is variable, and the grounding itself has not a straight line, but an arbitrary shape at a distance of less than 0.
NICHOLAS WOLTERSTORFF is concerned to find an appropriate grounding of human rights understood as inherent natural rights.
The potential number of groundings may be based on (Simonsen 1997):
Total expected number of groundings over a unit of time:
But the grounding of two foreign vessels one after the other in Tubbataha should be looked into, Gazmin said.
Both groundings destroyed the existing relief, creating large rubble fields from which large rubble was subsequently removed or stabilized during restoration activities (Marine Resources Inc.
Because most of the large vessel groundings and anchor damage events off Ft.
There is a methodology which takes into account the high level of uncertainty and randomness of groundings.
Fedoseenko computational capabilities make it possible to implement an algorithm for calculating non-equipotential complex combined groundings as a universal one.