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General Electric
Industry: Energy
Number of terms: 8202
Number of blossaries: 3
Company Profile:
American conglomerate currently ranked by Forbes as the world's largest company. GE has multifarious business interests including power generation and financial services.
Resistance of the cathode in a Fluorescent lamp. It is measured "cold" before the lamp is turned on (Rc) or "hot" after the lamp is turned on (Rh). The ratio of the hot resistance to the cold resistance is also measured (Rh/Rc).
Industry:Lights & lighting
Windings of copper or aluminum wire surrounding the steel core in ballast. Also refers to the entire assembly comprising the inductor or transformer.
Industry:Lights & lighting
A condition under which a gas becomes electrically conducting and becomes capable of transmitting current, usually accompanied by the emission of visible and other radiation. An electric spark in air is an example of an electrical discharge, as is a welder's arc and a lightning bolt. (See ARC, ELECTRODELESS LAMPS)
Industry:Lights & lighting
Any metal terminal emitting or collecting charged particles, typically inside the chamber of a gas discharge lamp. In a fluorescent lamp, the electrodes are typically metal filaments coated with special powders called emission mix. Negatively charged free electrons emitted by one electrode are attracted to the positive electrode (anode), creating an electric current and arc between electrodes.
Industry:Lights & lighting
A physical phenomenon whereby an atom of a material absorbs a photon of light an immediately emits a photon of longer wavelength. If there is a significant delay the phenomenon is called phosphorescence rather than fluorescence. It is interesting that "phosphors" used in lamps exhibit "fluorescence," not "phosphorescence." (See PHOSPHOR)
Industry:Lights & lighting
A high efficiency lamp utilizing an electric discharge through inert gas and low pressure mercury vapor to produce ultraviolet (UV) energy. The UV excites phosphor materials applied as a thin layer on the inside of a glass tube which makes up the structure of the lamp. The phosphors transform the UV to visible light.
Industry:Lights & lighting
Rate of alternation in an AC current. Expressed in cycles per second or Hertz (Hz).
Industry:Lights & lighting
Electromagnetic energy radiated in the wavelength range of about 770 to 1,000,000 nanometers. Energy in this range cannot be seen by the human eye, but can be sensed as heat by the skin.
Industry:Lights & lighting
Power supply voltage required for proper operation of fluorescent or HID ballast.
Industry:Lights & lighting
A unit of temperature starting from absolute zero, parallel to the Celsius (or Centigrade) scale. 0C is 273K.
Industry:Lights & lighting