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E or Edison Screw-in Sockets and Bases

E or Edison screw-in sockets and bases

Screw-in bases, also known as Edison bases and light bulb sockets are used through out the world. 

Bulb Bases and Sockets Explained - 2

The naming conventions include terms like medium base and candelabra base. Often they are referred to with a letter-number designation that starts with an "E" followed by the number of millimeters in diameter of the base. If your base ends in a "d" this indicates a double contact base, this is typically used for 3-way bulbs. 
Typically North American 120VAC bases and 240VAC bases differ by only a millimeter and carry the same full name in each country. Many EagleLight bulbs support both 120VAC and 240VAC, check specifications for the bulb to determine if the bulb supports 240VAC if your application requires that. 
"E" or Edison base types, sizes and names 
Base Number Diameter Base or Socket Name
E5 5mm Lilliput Edison Screw Base
E10 10mm Miniature Edison Screw Base
E11 11mm Mini-Candelabra Edison Screw Base
E12 12mm Candelabra Edison Screw Base
E14 14mm Small Edison Screw Base (supports 240V)
E17 17mm Intermediate Edison Screw Base
E26 26mm Medium Edison Screw Base
E27 27mm Medium Edison Screw Base (supports 240VAC)
E39 39mm Mogul or Giant Edison Screw Base
E40 40mm Mogul or Giant Edison Screw Base (supports 240VAC)

F or Flange light bulb base and sockets

 Bulb Bases and Sockets Explained - 2_1

LED light bulb flange base types. 

LED flanged bases include base types like: micro-midget flanged base, midget flanged, miniature midget flanged, sub-midget flanged, and special-midget flanged base types. These LED light bulb types are used in automotive and electronic device lighting applications. 

G or Bi-pin light bulb base and sockets

 Bulb Bases and Sockets Explained - 2_2

The "G" base type of lamp and light bulb is used to designate a "pinned" base. This can include several pin types and different numbers of pins. 

Designation is by letter(s)-numbers-optional letter: The first letters include "G" followed by an optional U, X, Y or Z. Next is a number that designates the number of millimeters between the center of each pin. Finally the optional final letter designates the number of pins, no letter implies 2 pins as does a d for double. Pin number designations include: s : Single, d : Double, t : Triple for 3 pins and q : Quadruple for 4 pins. 
Examples include: GU10 base type, G24q base type, or for T8 tubes G13 bi-pin. 

Type Pin to pin distance Pin Diameter Typical Bulbs that use this base
G4 4mm 0.65-0.75mm MR11 and other small halogens of 5/10/20 watt and 6/12 volt
GU4 4mm 0.95-1.05mm  
GY4 4mm 0.65-0.75mm  
GZ4 4mm 0.95-1.05mm  
G5 5mm   T4 and T5 fluorescent tubes
G5.3 GU5.3 GX5.3 GY5.3 5.33 mm 1.47-1.65mm MR16 and other small bulbs typically using 12/24 volts
G6.35 GX6.35 GY6.35 6.35 mm 0.95-1.3mm  
G8 8mm    
G9 9mm    
GU10 10mm   bulbs using twist-lock bi-pin base
G13 12.7mm   T8,T10 & T12 fluorescent tubes
G23 23mm 2mm  
GU24 24mm   2 and 4 pin bases with center key
GX53 53mm   used with puck shaped lamps typically twist-lock

K or Cable connected lights and lamps


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Bulb Bases and Sockets Explained - 2
Topics: Lighting