Bi-pin Lamp Base - Wikipedia

Type of lamp/lightbulb fitting/connector For other types of lightbulb mounts and sockets, see Lightbulb sockets.

A bipin or bi-pin (sometimes referred to as two-pin, bipin cap or bipin socket) is a type of lamp fitting. They are included in the IEC standard "IEC 60061 Lamp caps and holders together with gauges for the control of interchangeability and safety". They are used on many small incandescent light bulbs (especially halogen lamps), and for starters on some types of fluorescent lights.

Some sockets have pins placed closer together, preventing the low-power bulbs they use from being replaced by bulbs that are too high power, which may generate excessive heat and possibly cause a fire. These are sometimes called "mini-bipin". Where the terminals of the lamp are bent back onto the sides of the base of the bulb, this forms a wedge base, often used in small bulbs for automotive lighting.

The bi-pin base was invented by Reginald Fessenden for the 1893 World's Fair in Chicago.[citation needed] After Westinghouse won the contract to wire and illuminate the first electrified fair with AC instead of arch-rival Thomas Edison's DC, Edison and his General Electric company refused to allow his patented Edison screw-base bulbs to be used. Westinghouse overcame this by developing the bi-pin base for use at the fair. An incandescent electric lamp with a bi-pin base was patented by the Westinghouse (G. Westinghouse, Jr.) in 1895.[1][non-primary source needed]

Types

[edit]

Illustration	Designation	IEC 60061-1 sheet	Pin		Usage
			Pitch	Diameter
	G4	7004-72-3	4.0 mm	0.65–0.75 mm	Small halogen quartz capsules of 5/10/20 watt and 6/12 volt AC and DC.
GU4	7004-108-2	4.0 mm	0.95–1.05 mm	MR11 and MR8
GY4	7004-72A-1	4.0 mm	0.65–0.75 mm
GZ4	7004-67-3	4.0 mm	0.95–1.05 mm	MR11 and MR8
G5	7004-52-7	5 mm	T4 and T5 fluorescent tubes
	G5.3	7004-73-2	5.33 mm	1.47–1.65 mm
G5.3-4.8	7004-126-1
	GU5.3	7004-109-2	5.33 mm	1.45-1.6 mm
GX5.3	7004-73A-2	5.33 mm	1.45–1.6 mm	Round pins. MR16 and other small halogens of 20/35/50 watt and 12/24 volt.
	GY5.3	7004-73B-2	5.33 mm	—	Flat pins
	G6.35	7004-59-6	6.35 mm	0.95–1.05 mm
GX6.35	7004-59-6	6.35 mm	0.95–1.05 mm
GY6.35	7004-59-6	6.35 mm	1.2–1.3 mm	Halogen various wattage (e.g. 50 W/100 W), various voltage (e.g. 12/24 V). Common for task lighting, landscape lighting.
GZ6.35	7004-59A-3	6.35 mm	0.95–1.05 mm	projector bulb
G8	—	8.0 mm	1.0 mm	Halogen 35–100 W 120-240 V
GY8.6	—	8.0 mm	1.25 mm	Halogen up to 100 W, 120 V
	G9	7004-129-3	9.0 mm	Halogen 120 V (US) / 230 V (EU), also used for LED lamps.
G9.5	7004-70-2	9.5 mm	3.10–3.25 mm	Common for theatre use, several variants
	GU10	7004-121-2	10 mm	5 mm	Twist-lock 120/230-volt MR16 halogen lighting of 35/50 watt, since the mid-2000s. Also used for compact fluorescents and LED lamps.
GZ10	7004-120-1	10 mm	Twist-lock 120/230-volt MR16 halogen lighting of 35/50 watt, differs from GU10 by use of a dichroic reflector. GZ10 fixtures can use GU10 bulbs, but not vice versa.
G12	7004-63-2	12.0 mm	2.35 mm	Used in theatre and single-end metal halide lamps.
G13	7004-51-10	0.50 in (12.7 mm)	0.093 in (2.35 mm)	Common T8, T10 and T12 fluorescent tubes.
GX16d	"Mogul End Prong", common for theatre PAR lamps.
G23	7004-69-1	23 mm	2 mm
	GU24	7004-78-5	24 mm	Twist-lock for self-ballasted compact fluorescents, since the 2000s.
	G38	7004-76-1	38 mm	11.1 mm	Mostly used for high-power theatre lamps.
	GX53	7004-142-2	53 mm	Twist-lock for puck-shaped under-cabinet compact fluorescents and LED lamps, since the 2000s.
GX70	—	70 mm	Twist-lock for puck-shaped compact fluorescents or LED lamps.

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 a short section of larger diameter at the end (sometimes described as a "peg" rather than a "pin"[2]); the socket allows the bulb to lock into place by twisting it; in others, the base of the lamp has a groove which can be held by a spring or clip.[3]

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 that has a permanent ballast.

There are also double-ended halogen and fluorescent tubes with one pin at each end, and high-output fluorescents with recessed or shrouded contacts, which are not covered here.

• Halogen lamps with GU4 (left) and G4 (right) bases
• Halogen lamp with G6.35 base
• Metal halide lamp with G8.5 base
• Halogen lamp with G9 looped-pin base
• Halogen lamp with GU10 twist-lock base

See also

[edit]

• Bayonet mount
• Fluorescent-lamp formats
• Fluorescent lamp
• Multifaceted reflector (MR)

References

[edit]

1. ^ *U.S. patent 543,280, incandescent electric lamp
2. ^ Simon Brammer (28 March 2014). "Converting to LED lights: everything you need to know". The Guardian. Retrieved 20 November 2018.
3. ^ "index". Osram.com. 2012-03-09. Archived from the original on April 29, 2011. Retrieved 2012-04-25.

External links

[edit]

• Media related to Bipin at Wikimedia Commons
• Cross-reference for EU/US

v t e Lighting
Concepts	Accent lighting Color rendering index Color temperature Electric light Glare Light fixture Light pollution Hawaii Hong Kong Lightbulb socket Bi-pin lamp base Edison screw Luminous efficacy Task lighting
Methods of generation	Incandescent Regular Edison Halogen Nernst Luminescent Cathodoluminescent Electron-stimulated Chemiluminescent Electrochemiluminescence Electroluminescent field-induced polymer Fluorescent Fluorescent lamp (compact) Fluorescent induction Photoluminescent Laser headlamp Radioluminescence Solid-state LED lamp Combustion Acetylene/Carbide Argand Campfire Candle Carcel Diya Flare Gas Kerosene Petromax Lantern Fanous Paper Limelight Luchina Magnesium torch Oil Rushlight Safety Tilley Torch Electric arc Carbon arc Klieg light Yablochkov candle Gas discharge Deuterium arc Neon Neon lamp Plasma Sulfur Xenon arc Xenon flash High-intensitydischarge (HID) Mercury-vapor Metal-halide ceramic Hydrargyrum medium-arc iodide (HMI) Hydrargyrum quartz iodide (HQI) Sodium vapor
Stationary	Reflector Ellipsoidal reflector Multifaceted reflector Parabolic aluminized reflector (PAR) Aviation obstruction Balanced-arm lamp Chandelier Emergency light Gas lighting Gooseneck lamp Intelligent street lighting Light tube Nightlight Neon lighting Pendant light Recessed light Sconce Street light in the US Torchère Track lighting Troffer
Portable	Bicycle lighting Flashlight Mechanically powered Tactical Glow stick Headlamp outdoor Lantern Laser pointer Navigation light Searchlight Solar lamp
Automotive	Automotive light bulb types Daytime running lamp Headlamp hidden high-intensity discharge sealed beam Rear position lights Reversing lights Safety reflector retroreflector Stop lights Turn signals trafficators
Display Decorative	Aroma lamp Blacklight Bubble light Christmas lights Crackle tube DJ lighting Electroluminescent wire Lava lamp Marquee Plasma globe Strobe light
Theatrical Cinematic	Floodlight Footlight Gobo Scoop Spotlight ellipsoidal reflector Stage lighting instrument
Industrial Scientific	Germicidal Grow light Infrared lamp Stroboscope Tanning
Related topics	Battlefield illumination Bioluminescence Laser Light art Luminous gemstones Signal lamp Sources Reflected