Glossary of Terms


 B  C  G  H  L  N  O  P  Q  S  T 


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TermDefinitionPicture
 B
Ballast
Gear
The fundamental component of all discharge lighting circuits. A Ballast restricts both voltage and current flowing to the lamp it supplies. The traditional magnetic ballast consists of a single or multiple copper windings on a laminated iron core, either open or encased in an insulating compound such as resin. Switchstart ballasts are usually a single winding whereas SRS ballasts are double wound.
See also: SRS, QS, SS, HF
 
BLI
Company
Acronym: British Lighting Industries. 
 C
CFL
Lamp
Acronym: Compact Fluorescent Lamp.
See also: Compact Fluorescent Lamp
 
Compact Fluorescent Lamp
Lamp
A miniature fluorescent lamp, originally designed for retrofitting GLS lamps and alike, to reduce power consumption. A range of fittings followed which only took compact fluorescent lamps, which could be fitted where historically tungsten lamps would have been used as the source. For example, PL downlighters. 
Cooker Tube
Lamp
A specially made fluorescent tube, usually of T8 15w variant which was intended for use in built in lights found in standalone upright cookers. These tubes were usually of the Deluxe Natural colour and made by Thorn Lighting for the Tricity brand of cookers.View Image
 G
General Lighting Service
Lamp
Term generally given to a standard incandescent lamp used in homes and commercial premises. They usually resemble that which is shown in the example image.
See also: GLS
View Image
GLS
Lamp
Acronym: General Lighting Service.
See also: General Lighting Service
View Image
 H
HF
Gear
Acronym: High Frequency.
See also: High Frequency
 
High Frequency
Gear
Also known as Electronic Ballast. Developed during the early 1980s from the low voltage transistorised ballast circuits. An entirely electronic ballast circuit that operates the tube at a frequency of several thousand hertz, hence the name. Types include programmed start that preheat the tube for a predetermined time, instant start and dimmable types that work from either 0-10v control signals or a simple push button switch. Reliability issues have been known due to complex circuitry or poor quality.
See also: HF
 
High Pressure Sodium Lamp
Lamp
Sodium discharge operating in a sintered aluminium oxide arc tube to withstand the intense chemical activity at high temperature. Three types of outer bulb are available: 1/ SON, elliptical bulb with a diffusing coating, can be used in the same fitting as mercury lamps, but require different control gear. 2/ SON-T, tubular clear hard glass for floodlighting. 3/ SON-TD, tubular double ended clear quartz, the length and cap are equivalent to those of tungsten halogen lamps.View Image
HPS
Lamp
Acronym: High Pressure Sodium.
See also: High Pressure Sodium Lamp
View Image
 L
LED
Lamp
Acronym: Light Emitting Diode. 
LPS
Lamp
Acronym: Low Pressure Sodium. Low pressure sodium discharge operating in either, a U- shaped or linear arc tube enclosed in a tubular outer bulb which has an internal infa-red reflecting coating to provide thermal insulation for the discharge tube. 
 N
NAV
Lamp
High Pressure Sodium Lamp. NAV-E & NAV-T are terms usually used by Osram and Wotan for their high pressure sodium lamps.
See also: High Pressure Sodium Lamp
 
 O
Omega
Company
One of Thorn's budget brands, often supplied to OEM users and local authority clients as a lower cost option. 
 P
Polylux
Lamp
A trade name used by Thorn and later GE, for their range of Triphosphor fluorescent lamps. Lamp colours were defined by colour temperature. for example, a Thorn 3500K white Triphosphor lamp was known as Polylux 3500. The current 3 digit system consisting of the Colour Redndering Index number and colour temperature was established by GE in the early 1990s. 
 Q
QS
Gear
Acronym: Quickstart. 
 S
SL
Lamp
Range of electronic and magnetic ballasted compact fluorescent lamps brought out by Philips Lighting.
See also: CFL, Compact Fluorescent Lamp
View Image
SLI/H
Lamp
A linear, double ended SO (low pressure sodium lamp), designed for horizontal use only.
See also: LPS
 
SO/H
Lamp
A variant of the SO (low pressure sodium lamp) and predecessor to the SOX lamp, which had to be burnt only in the horizontal position.
See also: LPS
 
SON
Lamp
Alternative term for the High Pressure Sodium Lamp.
See also: High Pressure Sodium Lamp
 
SON-DL
Lamp
A SON lamp, usually elliptical in shape, specially made to produce a more appealing source of light. This is referred to as a deluxe (DL) SON lamp. 
SON-E
Lamp
Elliptical versions of SON / HPS lamps.
See also: High Pressure Sodium Lamp
View Image
SON-R
Lamp
Reflector versions of SON / HPS lamps.
See also: High Pressure Sodium Lamp
View Image
SON-T
Lamp
Tubular versions of SON / HPS lamps.
See also: High Pressure Sodium Lamp
View Image
SOX
Lamp
A variant of the SO (low pressure sodium) lamp.
See also: LPS
 
SS
Gear
Acronym: Switchstart.
See also: Switchstart
 
Switchstart
Gear
The traditional fluorescent circuit consisting of a ballast and starter switch. Upon switch-on, the starter closes and preheats the tube's cathode filaments. Upon opening, the magnetic field within the ballast collapses, causing a voltage pulse which strikes the tube. This is often repeated twice or more, causing the distinctive blinking at startup.
See also: SS, Ballast
 
 T
T5 / T8 / T9 / T10 / T12 / T17
Lamp
References to the standardised diameter of a fluorescent tube.