EARTH FAULT - A fault that occurs when a conductor is accidentally connected to earth or when the resistance to earth of an insulator falls below a specific value.
EARTH POTENTIAL - The potential of a large conducting body, such as the earth, taken to be the arbitrary zero in the scale of electrical potential. Synonymous with zero potential.
ECM - Abbreviation for Electronic Counter Measure. The use of equipment to prevent or induce jamming of electronic equipment, missile systems, radar, radio, and other devices.
ECTFE - Abbreviation for ethylene chlorotrifluoroethylene copolymer. See ethylene chlorotrifluoroethylene. Trade name Halar®. Halar® is a trademark of the Allied Chemical Co.
EEA - Abbreviation for ethylene-ethyl acrylate copolymer.
EHF - Abbreviation for extremely high frequency. See frequency band.
EIA - Abbreviation for Electronics Industries Association. Formerly know as RETMA (Radio Electronics Television Manufacturers Association).
ELASTOMER - A rubberlike substance.
ELECTRICAL DUCT - Any electrical conduit or other raceway round in cross section, approved or listed for use underground, and embedded in earth or concrete.
ELECTROMOTIVE FORCE - Pressure or voltage. The force which causes current to flow in a circuit. The algebraic sum of the potential differences in a circuit equals the EMF, which is measured by the energy liberated when unit electric charge passes completely round the circuit. A battery of EMF,
E, will supply a current, I, to an external resistance,
R:
E = I (R + r)
where
r is the internal resistance of the battery.
The term "electromotive force" strictly applies to a source of electrical energy but is sometimes misused as being equivalent to potential difference. Symbol
E. Abbreviated as
EMF.
ELECTROTINNED - Wire tinned with pure tin using an electrolytic process.
ELONGATION - The state of being elongated or lengthened.
