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Pair. Two
insulated wires of a single circuit associated together.
Pairing. The union of two insulated single
conductors through twisting.
Parallel Cable. Two insulated conductors
side-by-side in a cable.
PASP. An air core (unfilled) direct burial
telephone cable used in area subject to rodent attack.
It consists of an unfilled cable core, corrugated aluminum
shield, corrugated steel tape, flooding compound and polyethylene
jacket.
Peak Voltage. The maximum instantaneous
voltage.
Percent Conductivity. Conductivity of
a material expressed as a percentage of that of copper.
Periodicity. The uniformly spaced variations
in the insulation diameter of a transmission cable that
result in reflections of a signal, when its wavelength
or a multiple thereof is equal to the distance between
two diameter variations.
Permittivity. See dielectric constant.
Pick. Distance between two adjacent crossover
points of braid filaments. The measurement in picks per
inch indicates the degree of coverage.
Pitch Diameter. Diameter of a circle
passing through the center of the conductors in any layer
of a multiconductor cable.
Planetary Cabler. A cabler capable of
laying down any number of shielded, overbraided, or jacketed
singles, pairs, called groups, or any combination of them
in sequence.
Planetary Twister. A twisting machine
whose payoff spools are mounted in rotating cradles that
hold the axis of the spool in a fixed direction as the
spools are revolved so the wire will not kink as it is
twisted.
Plastic Deformation. Change in dimensions
under load that is not recovered when the load is removed.
Plasticizer. A chemical agent added to
plastics to make them softer and more pliable.
PLTC. NEC type designation for Power-
Limited Tray Cable for use in class 2 or 3 Power-Limited
circuits; instrumentation supervisory control, and thermocouple
extension.
Polyester. Polyethylene terephthalate
which is used extensively in the production of a high
strength moisture resistant film used as a cable core
wrap.
Polyethylene. A thermoplastic material
having the chemical identity of polymerized ethylene.
Polymer. A substance made of many repeating
chemical units or molecules. The term polymer is often
used in place of plastic, rubber, or elastomer.
Polyolefin. A family of thermoplastics
based upon the unsaturated hydrocarbons known as olefins.
When combined with butylene or styrene polymers they form
compounds such as polyethylene and polypropylene.
Polypropylene. A thermoplastic polymer
of propylene.
Polyvinyl Chloride (PVC). A thermoplastic
material composed of polymers of vinyl chloride which
may be rigid or elastomeric, depending on specific formulation.
PVC is one of the most common wire insulations.
P.O.S. Abbreviation for point-of-sale.
Power Factor. The ratio of resistance
to impedance. The ratio of the actual power of an alternating
current to apparent power. Mathematically, the cosine
of an angle between the voltage applied and the current
resulting.
Pre-Bond. Stranded wire which has been
fused, topcoat tinned, or overcoat tinned.
Primary Insulation. The first layer of
nonconductive material applied over a conductor, whose
prime function is to act as electrical insulation.
Progpagation Delay. Time required for
a signal to pass from the input to the output of a device.
Propagation Time. Time required for
an electrical wave to travel between two points on a transmission
line.
PTFE. Abbreviation for Polytetrafluoroethylene.
Pulse. A current or voltage which changes
abruptly from one value to another and back to the original
value in a finite length of time. Used to describe one
particular variation in a series of wave motions.
Pulse Cable. A type of coaxial cable
constructed to transmit repeated high voltage pulses without
degradation.
Pyrometer. See Thermocouple Thermometer.
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