Edison Screw Bases
This is a commonly used type of light bulb base. ‘E’ which stands for Edison often comes before the number that represents the diameter of the base.
Edison screw bases have threads that screw into a fixture. They are further categorized according to the diameter size which is measured in millimeters.
For those that need high potency such as street lights, you will use E20 mogul base.
In decorations fixtures you will use candelabra base where E12 is the diameter.
Use medium base E26 or E27 for your household lighting.
For other appliances, you will use an intermediate base with the diameter of E17.
Bayonet Bases
These bases are also known as swan socket. When letter’ B ‘which stands for bayonet is followed by a number, it provides more information about lamps specifications. These number also represents the diameter to the base which is measured in millimeters .Bayonet bases are mostly used in automotive industries where ‘BA15d’ is often used which is also known as push and twist base .However they can also be used in spotlights, ships and boats due to its high intensity.
Pin Bases
Just as the word states ‘pin’, might have one, two, three or four pins that you will use to connect directly into your fixed appliance and the voltage will just flow freely from the socket to the bulb. You will use these pin bases mainly in florescent bulbs and halogen bulbs.
Unlike other bases where the first letter in conjunction with a specific number represents the diameter of the base bulb, pin bases are represented by letter ‘G’ For halogen and LED bulbs, you will use small two pin bases which are represented by ‘ G4’ and ‘ G9 ‘. You will use ‘G13’ for your fluorescent tubes.
Unique Bases
On unique bases, we have bases for different specialty .
A Bi-pin base which is one of the unique bases is mostly used in linear fluorescent tubes’’ which is followed by a specific number represents the tube diameter. These representations include, T5, T8, and T12. For fluorescent tubes used in commercial lighting you will use ‘2G11’ four pin base. Otherunique bases include wedge base which is also used in automotive industries. We also have a pre-focus base that if for high intensity.
In conclusion, all these bases are designed for specific applications. They come in different various shapes and sizes depending on the specific fixture that they are designed for .Therefore it is essential to choose correctly on what suits you.