Pair
Two insulated wires of a single circuit associated together; also known as a "balanced" transmission line

Parallel Circuit
A circuit in which identical voltage is presented to all components, and the current divides among the components according to the resistances or the impedances of the components

Parallel Stripe
A stripe applied logitudinally on a wire or cable parallel to the axis of the conductor

Parallel Transmission
A type of data transfer in which all bits of a character, or multiple-bit data blocks, are sent simultaneously, either over separate communications lines or circuits, over a single channel using multiple frequencies, or over a multiple-conductor cable

Partial Discharge (Corona) Extinction Voltage
The voltage at which partial discharge (corona) is no longer detectable on instrumentation adjusted to a specific sensitivity, following the application of a specified higher voltage

Patch Cable
A cable with plugs or terminals on each end of the conductors to temporarily connect circuits of equipment together

Payoff
The process of feeding cable or wire from a bobbin, reel, or other package

PCB
Printed Circuit Board

PCP
Polychloroprene (Neoprene)

PDN
Public Data Network. A packet switched or circuit switched network available for use by many customers. PDNs may offer value-added services at a reduced cost because of communications resource sharing, and usually provide increased reliability due to built-in redundancy

PE
Polyethylene. A widely used thermoplastic insulation and jacket compound

Peak
The maximum instantaneous value of a varying current or voltage. Also called crest

Peek
Poly ether ether ketone

Peel Strength
The force necessary to peel a flexible member from another member which may be either flexible or rigid

Percent Conductivity
The ratio of the resistivity of the International Annealed Copper Standard (IACS) at 20ºC, expressed in percent. Results are calculated on a weight basisor volume basis and so specified

Percent Plating
Quantity of plating on a conductor expressed as a percentage by weight

Percentage Conductivity
Conductivity of a material expressed as a percentage of that of copper

PFA
Perfluoroalkoxy. Teflon is DuPont's trademark for this material

Phase
The location of a position on a waveform of an alternating current, in relation to the start of a cycle. Measured in degrees, with 360 corresponding to one complete cycle

Phase Sequence
The order in which successive members of a periodic wave set reach their positive maximum values:
a) zero phase sequence - no phase shift
b) plus/minus phase sequence - normal phase shift

Phase Shift
A change in the phase relationship between two alternating quantities. The phase angle between the input and output signals of a system

Pick
Distance between two adjacent crossover points of braid filaments. The measurement in picks per inch indicates the degree of coverage

Pico
Prefix meaning one-millionth of one -millionth (10 to the power of 12)

Picofarad
One-millionth of one-millionth of a farad. A micromicrofarad, or picofarad (abbreviation pf)

Pigtail Wire
Fine stranded, extra flexible, rope lay lead wire attached to a shield for terminating purposes

PILC Cable
Paper Insulated Lead Covered

Pin Assignment
A predetermined relationship between the terminals in a connector and the conductors in a cable that specifies the terminals to which each conductor is to be terminated

Pitch
In flat cable, the nominal distance between the index edges of two adjacent conductors

Pitch Diameter
Diameter of a circle passing through the center of the conductors in any layer of a multiconductor cable

Planetary Twister
A cabling machine whose payoff spools are mounting 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

Plasticizer
A chemical added to plastics to make them softer and more flexible

Plated Hole
A hole with walls that have been plated with conductive material to provide an electrical connection between the conductive patterns on both sides of a printed circuit or an anchor for soldering an inserted wire

Plenum
The air return path of a central air handling system, either ductwork or open space over a suspended ceiling

Plenum Cable
Cable approved by a recognized agency such as UL for installation in plenums without the need for conduit

PLTC
Power Limited Tray Cable, rated 300 volts

Plug
The part of the two mating halves of a connector which is movable when not fastened to the other mating half

Ply
The number of individual strands or filaments twisted together to form a single thread

Point-to-Point Wiring
An interconnecting technique wherein the connections between components are made by wires routed between connecting points

Polarization
The orientation of a flat cable or a rectangular connector

Polishing
Act of smoothing ends of optical fibers to an "optically smooth" finish, generally using abrasives

Polyamide
The chemical name for nylon

Polybutadiene
A type of synthetic rubber often blended with other synthetic rubbers to improve their properties

Polyester
Polyethylene terephthalate, used extensively as a moisture resistant cable core wrap. Mylar is DuPont's trademark for polyester

Polyethylene
A thermoplastic material having excellent electrical properties

Polyhalocarbon
A general name for polymers containing halogen atoms. The halogens are flourine, chlorine, bromine and iodine

Polyimide
A relatively high temperature plastic developed for use as a dielectric or jacketing material. Kapton is DuPont's trademark for polyimide

Polymer
A substance made of many repeating chemical units or molecules. The term polymer is often used in place of plastic, rubber or elastomer

Polymer Optical Fiber
One of the media projected to become the heart of an automotive LAN. The POF media would become the communications backbone of the vehicle

Polyolefins
A family of plastics including cross-linked polyethylene and various ethylene copolymers

Polypropylene
A thermoplastic similar to polyetyhlene but stiffer and having a higher temperature softening point

Polyurethane
Broad class of polymers notes for good abrasion and solvent resistance. Can be in solid or cellular form

Polyvinyl Chloride (PVC)
A general purpose thermoplastic used for wire and cable insulations and jackets

Porosity
Muliple voids in an insulation cross-section

Port
A point of access into a computer, a network, or other electronic device; the physical or electrical interface through which one gains acess; ther interface between a process and a communications or transmission facitlity

P.O.S.
Abbreviation for point-of-sale

Position Coding
Indentification of conductors by their location, possible only when conductors are located in assigned positions with rlation to each other throughout the entire length of a cable

POSJ
All rubber, parallel, light duty ripcord for us on lamps and small appliances - 300V, 60ºC

Potting
Sealing by filling with a substance to exclude moisture

Power
The amount of work per unit of time. Usually expressed in watts, and equal to I²R

Power Cables
Cables of various sizes, constructions, and insulations, single or multiconductor, designed to distribute primary power to various types of equipment

Power Factor
The cosine of the phase difference between current and applied voltage

Power Loss
The difference between the total power delivered to a circuit, cable, or device, and power delivered by that device to a load

Power Ratio
The ratio of the power appearing at the load to the input power. Expressed in db, it is equal to 10 log to the power of 10 (P2/P1) where P1 is input power and P2 is the power at the load

PPE
Polypropylene ethylene

Prebond
Stranded wire which has been fused, topcaoat tinned, or overcoat tinned

Premolded Splice
A joint made of premolded components assembled in the field

Primary
The transformer winding which receives the energy from a supply current

Primary Insulation
The first layer of nonconductive material applied over a conductor, whose prime function is to act as electrical insulation

Printing Wiring
A printed circuit intended to provide point-to-point electrical connections

ProductionTests
Tests mad on components during production for the purpose of quality control

Propagation Delay
The time it takes a signal, composed of electromagnetic energy to travel from one point to another over a transmission channel; usually most noticable in communicating with satellites; normally, the speed-of-light delay

Propagation Time
Time required for a wave to travel between two points on a transmission line

Propagation Velocity
The velocity of the propagation of a wave along a transmission path

Protective Covering
A field-applied material to provide environmental protection over a splice or housing, or both

Proximity Effect
Nonuniform current distribution over the cross-section of a conductor caused by the variation of the current in a neighbouring conductor

PT
Thermostat cable with solid conductor, individual insulation, twisted together

PTFE
Polytetrafluoroethylene. One type of Teflon. Sometimes abbreviated TFE

PTT
Post Telephone and Telegraph Authority. The government agency that functions as the communications common carrier and administrator in many areas of the world

Pulling Eye
A device used to pull cable into or from a duct

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

Pulse Cable
A type of coaxial cable constructed to transmit repeated high-voltage pulses without degradation

PVC
Polyvinyl chloride. A common insulating and jacketing material used on cables

PVC-I
A MIL-C-17 coax jacket type. A black polyvinyl chloride with excellent weathering and abrasion properties, but is a contaminating type and will cause cable attenuation to increase with age. Can be used for direct burial

PVC-II
A MIL-C-17 coax jacket type. A grey polyvinyl chloride material which is semi-noncontaminating

PVC-IIA
A MIL-C-17 coax jacket type. A black or grey polyvinyl chloride material which is noncontaminating. It has good weathering and abrasion-resistant properties and can be used for direct burial

PVDF
Polyvinylidene fluoride. Atochem's trademark for this material is Kynar

Pyrometer
See Thermocouple

Potentially Explosive Atmospheres
An explosive atmosphere is defined as a mixture:
- Of flammable substances in the form of gases, vapors, mists, dusts or fibers
- With air
- Under atmospheric conditions
- In which, after ignition has occurred, combustion spreads to the entire unburned mixture