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Alternating Current (AC): Electrical current which reverses directions at regular intervals
Amphere: the amount of electrical current that flows when 1 volt is applied to a resistance of 1 ohm
ANSI: American National Standards Institute; promotes knowledge and voluntary use of industry standards
AWG: American Wire Gauge; one of several standards defining conductor sizes; AWG standard: changes of 6 gauge sizes in solid conductor change diameter by a factor of 2; changes of 3 gauge sizes change the cross-sectional area by a factor of 2
Braid: woven covering of a cable made of textile or fine wire
Capacitance: property of a circuit element that permits it to temporarily store an electrical charge resulting in resistance to changes in voltage (see Farad)
Circular Mils: factor related to the cross-sectional area of a conductor, calculated as: diameter (in mils) squared
Concentric: having a common center; example: conductor in a coaxial cable
Corona: glowing ionized gas; in the case of high voltage cable, surrounding air that is ionized
Direct Current (DC): electrical current moving in one direction
Decibel: a unit expressing different levels of signal strength; in cables, the rate of loss of signal strength per unit of cable length expressed in decibels
Dielectric Constant: a measure of the inductive capacity of an insulating material as compared to that of a vacuum
EMF: Electro Motive Force; expressed as volts
Extrusion: pressure application of softened insulating material
Farad: a unit of capacitance in a circuit element expressing its opposition to changes in voltage
Fluoropolymer: any one of a series of polymers containing fluorine
Frequency: rate of change in polarity of an alternating current; usually expressed as cycles per second (see Hertz)
Halogen Free: containing none of five chemically related, non-metallic elements: fluorine, chlorine, bromine, iodine, and astatine
Henry: a unit of inductance equal to 1 volt of induced EMF while the inducing current is changing at the rate of 1 ampere per second (see inductance)
Hertz: cycles per second; specifically the number of times per second an alternating current changes direction; often expressed as kilohertz (thousands), megahertz (millions), and gigahertz (billions)
Hygroscopic: tendency of a material to absorb moisture; in the case of insulating materials, such tendency can change the processing and electrical properties of the material
Impedance: property of a circuit or element to resist the flow of an alternating current taking into account the circuit's resistance as well as its capacitance and inductance
Inductance: the tendency of a circuit to oppose changes in the amount of current flowing in the circuit, measured in Henrys
ISA: Instrument Society of America; professional society of the instrumentation industry
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Lay: refers to twists in multi-strand wire or cable; usually expressed in number of 360º turns per inch of foot
Loop Resistance: usually used in connection with thermocouple wire where positive and negative conductors are of different alloys having different resistances so that their combined resistance must be considered
Multi-Conductor: a cable containing 2 or more conductors
Multi-Pair: a cable containing 2 or more pairs of conductors
NIST: National Institute of Standards and Technology, formerly the National Bureau of Standards; a U.S. government agency that sets measurement and material standards and maintains reference specimens for its standards
Nickel Plated: Conductors or other circuit elements coated with nickel; expressed as a percentage, usually to a maximum of 27%
OFHC: Oxygen free high conductivity copper; used where purity and maximum conductivity are needed as in thermocouple circuits
Ohm: unit of resistance; expressed as the resistance of a circuit element wherein 1 ampere will flow when an EMF of 1 volt is applied across the element
Ohm's Law: defines the relationship between current (amperes), EMF (volts) and resistance (ohms); usually stated as: Amperes (l) = Volts (E) ÷ Ohms (R); or l = E/R
Ozone: an unstable gaseous form of oxygen composed of 3 atoms of oxygen; sometimes generated in high voltage circuits; ozone is chemically highly reactive and can be detrimental to circuit elements
Parallel Cable Construction: constructions where the conductors are not twisted but lay parallel to each other
Parallel Circuits: Circuit layout where an EMF can be applied to each element independently such that as elements are added to the circuit, resistance will fall and current flow will increase
Phase: used in reference to an alternating current, phase refers to the angular position of the rotating generator coil in relation to the zero line of the sinusoidal power curve
Pic: in the case of braided material, pic refers to the intersection of the crossing yarn/pics per inch refers to the tightness of the braid and is related to the degree (percent) of coverage
Resistance: tendency of a circuit element to resist the flow of electrons; usually expressed in Ohms
Resonance: the sympathetic response of an unpowered circuit or element having the same natural frequency as a powered element or circuit
Semi-Conductive: a term applied to a group of materials having conductive properties between usual conductors and insulators; these materials are sometimes used as screening to reduce radio frequency losses from a cable
Series Circuits: arrangement of circuit elements such that current must pass through each element in turn; as elements are added, resistance is increased and current flow is decreased
Specific Gravity: density of material expressed as a ratio relating it to the density of water |
