Bipin
Encyclopedia
International Electrotechnical Commission
The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...
for lamp fittings. These are used on many small incandescent light bulb
Incandescent light bulb
The incandescent light bulb, incandescent lamp or incandescent light globe makes light by heating a metal filament wire to a high temperature until it glows. The hot filament is protected from air by a glass bulb that is filled with inert gas or evacuated. In a halogen lamp, a chemical process...
s (especially halogen lamp
Halogen lamp
A halogen lamp, also known as a tungsten halogen lamp, is an incandescent lamp with a tungsten filament contained within an inert gas and a small amount of a halogen such as iodine or bromine. The chemical halogen cycle redeposits evaporated tungsten back on to the filament, extending the life of...
s), and on most fluorescent lights as well, where the filaments
Incandescent light bulb
The incandescent light bulb, incandescent lamp or incandescent light globe makes light by heating a metal filament wire to a high temperature until it glows. The hot filament is protected from air by a glass bulb that is filled with inert gas or evacuated. In a halogen lamp, a chemical process...
are involved in starting the tube when it is turned on.
Some lamps have pins placed closer together, preventing them from being interchanged with bulbs that are too high power
Electric power
Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...
, which may cause excessive heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
and possibly fire
Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition....
. These are sometimes called "mini-bipin". Some of these, particularly in automotive lighting
Automotive lighting
The lighting system of a motor vehicle consists of lighting and signalling devices mounted or integrated to the front, sides, rear, and in some cases the top of the motor vehicle...
, have the pins bent back onto the sides of the base of the bulb, this is instead called a wedge base
Wedge base
A wedge base is a type of electrical connector used as a fitting for small light bulbs. It is similar to the bi-pin connector, except that the two "pins" are the same wires that extend into the bulb , and the wires are bent up onto the sides of the base, where they make contact with the socket...
or socket.
The bi-pin base was invented by Reginald Fessenden
Reginald Fessenden
Reginald Aubrey Fessenden , a naturalized American citizen born in Canada, was an inventor who performed pioneering experiments in radio, including early—and possibly the first—radio transmissions of voice and music...
for the 1893 World's Fair in Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...
. After Westinghouse
Westinghouse Electric (1886)
Westinghouse Electric was an American manufacturing company. It was founded in 1886 as Westinghouse Electric Company and later renamed Westinghouse Electric Corporation by George Westinghouse. The company purchased CBS in 1995 and became CBS Corporation in 1997...
won the contract
Contract
A contract is an agreement entered into by two parties or more with the intention of creating a legal obligation, which may have elements in writing. Contracts can be made orally. The remedy for breach of contract can be "damages" or compensation of money. In equity, the remedy can be specific...
to wire and illuminate the first electrified fair with Nikola Tesla
Nikola Tesla
Nikola Tesla was a Serbian-American inventor, mechanical engineer, and electrical engineer...
's AC
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
instead of archrival Thomas Edison
Thomas Edison
Thomas Alva Edison was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. In addition, he created the world’s first industrial...
's DC
Direct current
Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
, Edison and his General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
company refused to allow his patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
ed Edison screw
Edison screw
The Edison screw fitting is a system of connectors used for light bulbs, developed by Thomas Edison and licensed starting in 1909 under the Mazda trademark. Most have a right-hand threading, so that it goes in when turned clockwise and comes out when turned counterclockwise, like a hardware screw...
-base bulbs to be used. Westinghouse overcame this by inventing the bi-pin base to use at the fair.
Codes
| Type | Standard | Pin centre to centre Centre-to-centre distance Centre-to-centre distance is a concept for distances, also expressed as hart distance. It is also called pitch.It is the distance between the centre of a column or pillar and the centre of another column or pillar. By expressing a distance in c.t.c., one can measure distances between pillar and... | Pin diameter Diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle... | Usage |
|---|---|---|---|---|
| G4 | IEC 60061-1 (7004-72) | 4.0 mm | 0.65-0.75 mm | MR11 and other small halogens of 5/10/20 watt and 6/12 volt |
| GU4 | IEC 60061-1 (7004-108) | 4.0 mm | 0.95-1.05 mm | |
| GY4 | IEC 60061-1 (7004-72A) | 4.0 mm | 0.65-0.75 mm | |
| GZ4 | IEC 60061-1 (7004-64) | 4.0 mm | 0.95-1.05 mm | |
| G5 | IEC 60061-1 (7004-52-5) | 5 mm | T4 and T5 fluorescent tubes | |
| G5.3 | IEC 60061-1 (7004-73) | 5.33 mm | 1.47-1.65 mm | |
| G5.3-4.8 | IEC 60061-1 (7004-126-1) | |||
| GU5.3 | IEC 60061-1 (7004-109) | 5.33 mm | 1.45-1.6 mm | |
| GX5.3 | IEC 60061-1 (7004-73A) | 5.33 mm | 1.45-1.6 mm | MR16 and other small halogens of 20/35/50 watt and 12/24 volt |
| GY5.3 | IEC 60061-1 (7004-73B) | 5.33 mm | ||
| G6.35 | IEC 60061-1 (7004-59) | 6.35 mm | 0.95-1.05 mm | |
| GX6.35 | IEC 60061-1 (7004-59) | 6.35 mm | 0.95-1.05 mm | |
| GY6.35 | IEC 60061-1 (7004-59) | 6.35 mm | 1.2-1.3 mm | Halogen 100W 120V |
| GZ6.35 | IEC 60061-1 (7004-59A) | 6.35 mm | 0.95-1.05 mm | |
| G8 | 8.0 mm | Halogen 100W 120V | ||
| GY8.6 | 8.6 mm | Halogen 100W 120V | ||
| G9 | IEC 60061-1 (7004-129) | 9.0 mm | Halogen 120V (US) / 230V (EU) | |
| G9.5 | 9.5 mm | 3.10-3.25 mm | Common for theatre use, several variants | |
| GU10 | 10 mm | Twist-lock 120/230-volt Volt The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the... MR16 halogen lighting of 35/50 watt, since mid-2000s |
||
| G12 | 12.0 mm | 2.35 mm | Used in theatre and single-end metal halide lamps | |
| G13 | 12.7 mm | T8 and T12 fluorescent tubes | ||
| G23 | 23 mm | 2 mm | ||
| GU24 | 24 mm | Twist-lock for self-ballasted compact fluorescents, since 2000s | ||
| G38 | 38 mm | Mostly used for high-wattage theatre lamps | ||
| GX53 | 53 mm | Twist-lock for puck Puck (sports) A puck is a disk used in various games serving the same functions as a ball does in ball games. The best-known use of pucks is in ice hockey, a major international sport.- Etymology :The origin of the word "puck" is obscure... -shaped under-cabinet Cabinet (furniture) A cabinet is usually a box-shaped piece of furniture with doors or drawers for storing miscellaneous items. Some cabinets stand alone while others are built into a wall or are attached to it like a medicine cabinet. Cabinets are typically made of wood or, now increasingly, of synthetic... compact fluorescents, since 2000s |
The suffix after the G indicates the pin spread; the G dates to the use of Glass for the original bulbs. GU usually also indicates that the lamp provides a mechanism for physical support by the luminaire: in some cases, each pin has two diameters, being larger near the ends, in order to twist-lock into position in the socket (the transition between the two diameters is a right-angle step rather than a taper
Taper
In cymbal making, taper refers to the gradual change in thickness from the bell to the rim of the cymbal. It is one of the key features that determines the tone of the cymbal....
); in others, the base of the lamp has a groove which can be held by a spring or clip.
A lowercase "q" at the end of the designation indicates that it is a quad-pin base, with two bi-pin pairs. These are used with compact fluorescent tubes that plug into a light fixture
Light fixture
A light fixture, light fitting, or luminaire is an electrical device used to create artificial light and/or illumination, by use of an electric lamp...
that has a permanent ballast.
There are also double-ended tubes (both halogen and fluorescent) with one pin at each end, as well as high-output fluorescents with recessed or shrouded contacts, which are not covered here.