ground current
the current that flows in
a power system in a loop involving earth and
(in some usages) other paths apart from the
three phases.
ground fault interrupter
a protective
device used in commercial and residential
wiring which monitors equipment connected
to an electrical outlet and shuts off the power
when a ground fault in the equipment is de-
tected.
ground fault neutralizer
an inductor
connected between the neutral of Y windings
of a generator or transformer and ground. It
is tuned to the machine’s capacitance so as to
minimize ground fault current.
ground lamp
indicator lamp on electrical
distribution switchboards that darkens when
a ground condition exists on one (or more) of
the busses.
ground loop
an undesired conductive path
between two conductive bodies in a radial
grounding system that are connected to a
common ground.
ground plane
a perfectly or highly con-
ducting half space beneath an antenna. Also,
an unetched layer of metal on a printed circuit
board over which microstriplines and printed
antennas are formed.
ground rod
a metallic, rod-type electrode
designed to be driven into the earth. It serves
as an earth connection for grounding pur-
poses. Other types of earth electrodes in-
clude buried plates, rings, and grids. For
buildings, its primary function is to keep the
entire grounding system at earth potential.
ground wave
a vertically polarized TEM
wave propagating close to the ground.
It
is one of the three modes of propagation
(ground, sky, and space waves).
ground-fault circuit interrupter (GFCI)
a device designed to detect ground-fault cur-
rent above a threshold value (several mil-
liamperes) and then interrupt the source of
electrical power by opening a circuit breaker
or a set of contacts. GFCIs are designed for
personnel protection and are generally avail-
able in the form of circuit breakers and re-
ceptacles.
ground-signal-ground (GSG)
(1) config-
uration of the contact tips of a coplanar mi-
crowave probe. A single signal contact is po-
sitioned in the center of two parallel ground
plane contacts.
(2) a network of wires buried in the earth
around a electric power transmission line
tower to reduce footing impedance.
grounded system
an electrical distribu-
tion system in which one of the normal
current-carrying conductors, often the neu-
tral, is intentionally grounded.
grounding
See
ground
.
grounding transformer
a transformer
connected to an otherwise ungrounded three-
phase system for the purpose of providing a
path for ground current flow. Zig-zag trans-
formers and grounded wye-delta transform-
ers can be used as grounding transformers.
group code
a recording method used for
6250 bpi (bits per inch) magnetic tapes.
group decision support system
a special
decision support system used in support of
groups of decision makers that might be ge-
ographically dispersed.
group delay
the derivative of the radian
phase with respect to frequency.
group detection
a special strategy for
multiuser detection in a multiple access sys-
tem. The users get divided into a number
of detection groups according to an appro-
priate criterion. The users in the designated
first group are detected using a predetermined
detection technique; the corresponding mul-
c
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