Glossary of Wire & Cable Terminology

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



D

db - Abbreviation for decibel(s). See decibel.

db LOSS - The loss of signal over a path or conductor, expressed in decibels.

DC - Abbreviation for direct current. See direct current. Also abbreviated dc.

DCR - Abbreviation for direct current resistance. The resistance offered by any circuit to the flow of direct current.

DEC - Abbreviation for Digitial Equipment Corporation.

DECA - A prefix to a unit, denoting a multiple of ten (10) of that unit.

DECI - A prefix to a unit, denoting a sub­multiple of one-tenth (10 -1) of that unit.

DECIBEL - A unit used to express ratios of sound or signal power, defined by the following formula where n is the number of decibels.

n = 10 log10 ( P2 / P1 )

Where P1 and P2 are the power levels. Since decibels represent a ratio, it is necessary to establish a refer- ence level in order to indicate an absolute level. For sound, the reference level is a pressure of 0.0002 microbar. Abbreviated as db.

DEGREE RISE - The amount of increase in temperature caused by the introduction of electricity into a unit.

DELAY LINE - A conductor that is made of a specific material in a specific size and length that will permit the delay of an electrical impulse for a predetermined specific length of time. The delay is measured in microseconds or nanoseconds.

DENSITY - The distribution of a quantity (as mass, electricity, or energy) per unit, usually of space.

DESICCANT - Water or moisture absorbent material used to prevent moisture from damaging packaged equipment or other merchandise.

DESIGN VOLTAGE - Voltage at which a cable is designed for maximum work.

DETECTA-DUCT - Traffic signal inductance loop detector wire. Detecta-Duct is a trademark of the Standard Wire & Cable Co.

DIA. - Abbreviation for diameter.

DIELECT. - Abbreviation for dielectric. See dielectric.

DIELECTRIC - Any insulating material that is a nonconductor of electricity. Abbreviated as dielect.

DIELECTRIC ABSORPTION - That property of an imperfect dielectric whereby there is an accumulation of electric charge within the body of the material when it is placed in an electric field.

DIELECTRIC CONSTANT - The factor by which the electric field strength in a vacuum exceeds that in the dielectric for the same distribution of charge. Symbol K. The K for air is 1.0.

DIELECTRICLOSS - Energy dissipated as heat when the dielectric is placed in a varying electric field.

DIELECTRIC STRENGTH -The maximum potential gradient (volts per mil) a dielectric will stand without breaking down the voltage stress required to puncture an insulation of known thickness (in volts per unit, usually volts per mil.)

DIGITAL - Of or relating to calculation by numerical methods or by discrete units. Opposite - analog.

DIODE - Any electronic device that has only two electrodes. There are several different types of diodes, their voltage characteristics determining their application. Diodes are most commonly used as rectifiers.

DIRECT BURIAL CABLE - A cable installed directly in the earth without use of an underground conduit. Also called "burial cable".

DIRECT CURRENT - A direct current is one which flows in one direction. Further classifications of direct currents are: a) Continuous currents which are steady, non pulsating direct currents: b) Constant currents, which continue to flow for a considerable time in the same direction and with unvarying intensity; and c) Pulsating currents, which are regularly varying continuous currents. Abbreviations DC and dc.

DIRECTION OF LAY - The lateral direction in which the strands of a cable run over the top of the cable as they recede from you looking along the axis of the cable.

DISPERSION - A general term for those phenomena that cause a broadening or spreading of light as it propagates through an optical fiber. The three types are modal, chromatic, and waveguide.

DOD - Abbreviation for the U. S. Department of Defense.

DOUBLE SHIELD - Two shields, one over the other. Maximum coverage is 98%.

DP - Abbreviation for data processing.

DRAIN WIRE - An uninsulated solid or stranded tinned copper wire which is placed directly under a shield. It touches the shield throughout the cable, and, therefore, may be used in terminating the shield to ground. A big labor saver in terminating all shield­ed cables. It is completely necessary on spiral shielded cables because it eliminates the possibility of induction in a spiral shield.

DRAWING - In wire manufacturing, pulling of metal through a die or series of dies to reduce diameter to a specific size.

DROP CABLE - In a CATV system, the transmission cable from the distribution cable to a dwelling.

DUCT - An underground or overhead tube for carrying electrical conductors.

DUPLEX - Two conductors twisted together, usually with no outer covering. This word has a double meaning and it is possible to have parallel wires and jacketed parallel wires and still refer to them as a duplex.

Site created by ThomasNet Web Solutions, a division of ThomasNet.com
Toll-Free: 800.326.0006The Electronic Wire and Cable Specialist for Over 60 Years