Wire
A rod or
filament of drawn or rolled metal whose length is great in comparison with the
major axis of its cross section. The definition restricts the term to what
would ordinarily be understood by the term solid wire.
In the
definition, the word slender is used in the sense that the length is great in
comparison with the diameter. If a wire is covered with insulation, it is
properly called an insulated wire, while primarily the term wire refers to the
metal; nevertheless, when the context shows that the wire is insulated, the
term wire will be understood to include the insulation.
Conductor
A wire or
combination of wires not insulated from one another, suitable for carrying an
electric current. The term conductor is not to include a combination of
conductors insulated from one another, which would be suitable for carrying
several different electric currents.
Rolled
conductors (such as bus bars) are, of course, conductors but are not considered
under the terminology here given.
Stranded
Conductor
A
conductor composed of a group of wires, usually twisted, or any combination of
groups of wires. The wires in a stranded conductor are usually twisted or
braided together.
Cable
A stranded
conductor (single-conductor cable) or a combination of conductors insulated
from one another (multiple-conductor cable). The component conductors of the
second kind of cable may be either solid or stranded, and this kind of cable
may or may not have a common insulating covering.
The first
kind of cable is a single conductor, while the second kind is a group of
several conductors. The term cable is applied by some manufacturers to a solid
wire heavily insulated and leads covered; this usage arises from the manner of
the insulation, but such a conductor is not included under this definition of
cable.
The term
cable is a general one, and in practice, it is usually applied only to the
larger sizes. A small cable is called a stranded wire or a cord, both of which
are defined below.
Cables may
be bare or insulated, and the latter may be armored with lead or with steel
wires or bands.
Strand
One of the
wires of any stranded conductor.
Stranded
Wire
A group of
small wires used as a single wire. A wire has been defined as a slender rod or
filament of drawn metal. If such a filament is subdivided into several smaller
filaments or strands and is used as a single wire, it is called stranded wire.
There is no sharp dividing line of size
between a stranded wire and a cable. If used as a wire, for example, in winding
inductance coils or magnets, it is called a stranded wire and not a cable. If
it is substantially insulated, it is called a cord, defined below.
Cord
A small
cable, very flexible and substantially insulated to withstand wear. There is no
sharp dividing line in respect to size between a cord and a cable, and likewise
no sharp dividing line in respect to the character of insulation between a cord
and a stranded wire. Usually the
insulation of a cord contains rubber.
Concentric
Strand
A strand
composed of a central core surrounded by one or more layers of helically laid
wires or groups of wires.
Concentric-Lay
Conductor
Conductor
constructed with a central core surrounded by one or more layers of helically
laid wires.
Rope-Lay
Conductor
Conductor
constructed of a bunch-stranded or a concentric-stranded member or members, as
a central core, around which are laid one or more helical layers of such
members.
N-Conductor
Cable
A
combination of N conductors insulated from one another. It is not intended that
the name as given here actually be used. One would instead speak of a
“3-conductor cable,” a “12-conductor cable,” etc. In referring to the general
case, one may speak of a “multipleconductor cable.”
N-Conductor
Concentric Cable
A cable
composed of an insulated central conducting core with N-1 tubular-stranded
conductors laid over it concentrically and separated by layers of insulation.
This kind
of cable usually has only two or three conductors. Such cables are used in
carrying alternating currents. The remark on the expression “N conductor” given
for the preceding definition applies here also. (Additional definitions can be
found in ASTM B354.)
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