Glossary – E

Efflorescence: An encrustation of soluble salts, commonly deposited on the surface of stone, brick, plaster, or mortar; usually caused by free alkalies leached from mortar or adjacent concrete as moisture moves through it.

 

Electric Circuit: A path that allows electric current to flow. Types of electric circuits include series, parallel, and series-parallel circuits.

 

Electric Power: The rate, per unit time, at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second. Electric power is usually produced by electric generators, but can also be supplied by sources such as electric batteries.

 

Electric Pressure: Voltage is the electric force or pressure that is required. Voltage is determined by the potential difference between any two points in a circuit.

 

Emittance or Emissivity (E): The ratio of the infrared energy emitted by an object compared to a blackbody at the same wavelength and temperature. Emittance is specified as a number between 0 and 1. (2) The measure of how well an object radiates IR energy when compared to a blackbody at same wavelength and temperature.

 

Enclosures of Motors: Motor enclosures may be open type (OT) or totally enclosed (TE). Open-type motors may have ventilation openings in the end shields and/or the shell. Totally enclosed motor enclosures may be non-vent (TENV) with no external fan, fan cooled (TEFC), and explosive proof.

 

End User: The person who actually uses a particular product or service, in this case, the results from an infrared thermographic inspection.

 

Energy: Ability to do work. Measured in foot-pounds in the English system and joules in the metric system. A foot- pound equals about 1.356 joules.

 

EPDM: See Ethylene Propylene Diene Monomer.

 

Equine: Relating to or affecting horses or other members of the horse family.

 

Ethylene Propylene Diene Monomer (EPDM): A type of synthetic rubber known as an elastomer, and characterized by a wide range of applications. The M refers to its classification in ASTM standard D- 1418; which includes rubbers having a saturated chain of the polymethylene type.

 

Exception: (1) A person or thing that is excluded from a general statement or does not follow a rule. (2) An usually warm or cool surface that may indicate a potential problem for the end user.

 

Expansion Joint: (1) A structural separation or flexible connection between two building elements that allows free movement of the elements without damage to the roof or waterproofing system. (2) A joint or gap (as in concrete work) designed to permit expansion or contraction resulting from temperature changes. (3) A coupling (as of steam pipes) designed to permit an endwise movement that compensates for expansion or contraction resulting from temperature changes.