Glossary

All | # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
There are 30 names in this directory beginning with the letter R.
R-F
Radio-Frequency

Raceway
An enclosed channel designed expressly for holding conductors and cables, including conduit and tubing, wireways and busways.

Rated Temperature
The maximum temperature at which an electrical component can operate for extended periods without undue degradation or safety hazard.

Rated Voltage
The maximum voltage at which an electrical component can be operated for extended periods without undue degradation or safety hazard.

Reactance
A measure of the combined effects of capacitance and inductance on an alternating current. The amount of such opposition varies with the frequency of the current. The reactance of a capacitor decreases with an increase in frequency. The opposite occurs with an inductance.

Receptacle
A contact device installed at an electrical outlet for the connection of a single attachment plug.

Red Plague
A powdery brown-red oxide of silver formed with water or rocket fuel fumes. It is highly conductive and can flake off and cause shorts in electrical equipment.

Redraw
The consecutive drawing of wire through a series of dies to reach a desired wire size.

Reel
A revolvable flanged device made of wood or metal, used for winding flexible metal wire or cable.

Reflection Loss
The part of a signal which is lost due to reflection of power at a line discontinuity.

Reinforced Sheath
The outermost covering of a cable that has cable sheath constructed in layers with the addition of a reinforcing material, usually a braided fiber, molded in place between layers

Resilient
The property of a substance to return to its original configuration after release of an applied force.

Resistance
A measure of the difficulty in moving electrical current through a medium when voltage is applied. It is measured in ohms.

Resistive Conductor
A conductor with high electrical resistance.

Resistivity
The longitudinal electrical resistance of a conductor of unit length and unit cross-sectional area, expressed in ohms-circular-mils per foot; the opposite of conductivity.

Retractile Cable
A coiled cable that returns by its own stored energy from an extended condition to its original retracted form.

Return Wire
A ground wire or the negative wire in a direct-current circuit.

RFI
Radio Frequency Interference.

RG/U
General utility-grade military coaxial cable.

Ribbon Cable
A cable composed of individually insulated conductors laid parallel and held together by extrusion, bonding or woven textile yarn.

Rip-Cord
Two or more insulated conductors in a parallel configuration which may be separated to leave the insulation of each conductor intact.

Rod
The solid round metallic form of copper and aluminum which is the most effective shape from which to draw wire.

RoHS
The Restriction of Hazardous Substances Directive 2002/95/EC, short for Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment, was adopted in February 2003 by the European Union restricting the use of Hazardous Substances.

Rope Concentric
A group of standard conductors assembled in a concentric manner.

Rope Lay Cable
A concentric, stranded cable designed for flexibility with its individual members made up of strands which are either concentric stranded or bunched.

Rope Lay Conductor
A conductor composed of a central core surrounded by one or more layers of helically-laid groups of wires.

Rope Unilay
A group of stranded conductors assembled in a unilay manner.

RPM
Revolutions Per Minute

Rubber (Wire Insulation)
Term used to describe wire insulations made of thermosetting elastomers, occur naturally or may be made synthetically.

Rupture
That point at which a material exceeds its elastic limit and physically comes apart as opposed to yield strength, elongation, etc.