Page 331 - Electrical Engineering Dictionary

ground current the current that flows in rent above a threshold value (several mil-
a power system in a loop involving earth and liamperes) and then interrupt the source of
(in some usages) other paths apart from the electrical power by opening a circuit breaker
three phases. or a set of contacts. GFCIs are designed for
personnel protection and are generally avail-
ground fault interrupter a protective able in the form of circuit breakers and re-
device used in commercial and residential ceptacles.
wiring which monitors equipment connected
to an electrical outlet and shuts off the power ground-signal-ground(GSG) (1)config-
when a ground fault in the equipment is de- uration of the contact tips of a coplanar mi-
tected. crowave probe. A single signal contact is po-
sitioned in the center of two parallel ground
ground fault neutralizer an inductor plane contacts.
connected between the neutral of Y windings (2) a network of wires buried in the earth
of a generator or transformer and ground. It around a electric power transmission line
is tuned to the machine’s capacitance so as to tower to reduce footing impedance.
minimize ground fault current.
grounded system an electrical distribu-
ground lamp indicator lamp on electrical tion system in which one of the normal
distribution switchboards that darkens when current-carrying conductors, often the neu-
a ground condition exists on one (or more) of tral, is intentionally grounded.
the busses.
grounding See ground.
groundloop anundesiredconductivepath
between two conductive bodies in a radial grounding transformer a transformer
grounding system that are connected to a connected to an otherwise ungrounded three-
common ground. phase system for the purpose of providing a
path for ground current flow. Zig-zag trans-
ground plane a perfectly or highly con- formers and grounded wye-delta transform-
ducting half space beneath an antenna. Also, ers can be used as grounding transformers.
an unetched layer of metal on a printed circuit
board over which microstriplines and printed group code a recording method used for
antennas are formed. 6250 bpi (bits per inch) magnetic tapes.

ground rod a metallic, rod-type electrode group decision support system a special
designed to be driven into the earth. It serves decision support system used in support of
as an earth connection for grounding pur- groups of decision makers that might be ge-
poses. Other types of earth electrodes in- ographically dispersed.
clude buried plates, rings, and grids. For
buildings, its primary function is to keep the group delay the derivative of the radian
entire grounding system at earth potential. phase with respect to frequency.

ground wave a vertically polarized TEM group detection a special strategy for
wave propagating close to the ground. It multiuser detection in a multiple access sys-
is one of the three modes of propagation tem. The users get divided into a number
(ground, sky, and space waves). of detection groups according to an appro-
priate criterion. The users in the designated
ground-fault circuit interrupter (GFCI) firstgrouparedetectedusingapredetermined
a device designed to detect ground-fault cur- detection technique; the corresponding mul-

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