Litetronics International

Litetronics RSS
You are here Lighting Knowledge

Light Bulb Bases Guide Part 2: Pin Bases

Share
There are two main types of light bulb bases: screw bases and pin bases. Each works in a different way to connect the light bulb to the electrical voltage in order to light the bulb.  In this article, we will discuss pin bases.  To learn about screw bases, click here.

Pin bases are used in MR16s, linear fluorescents, plug-in compact fluorescent bulbs, and some HID light bulbs. Whereas the screw base connects the light bulb to the voltage with two soldered contact wires on the metal base, pin base light bulbs have two pins sticking out of the base that connect the light bulb to the voltage. Electrical current then flows through the pins and into the light bulb to energize the filament or ballast to generate light.
lk_base_gu53lk_base_gu10
The names of pin bases include a number that measures the distance in millimeters between the two pins from center point to center point. For example, bi-pin GU5.3 bases have two pins that are 5.3 millimeters apart between the center points of each pin. This base and bi-pin GU10 are used in MR16 light bulbs.
lk_base_medbipin-g13lk_base_singlepin-fa8lk_base_r17dlk_base_mini-bi-pinslk_base_g12lk_base_r7s-rsc
Medium bi-pin G13
bases are used in the vast majority of T8, T10, and T12 linear fluorescent light bulbs. Some linear fluorescents have a single pin Fa8 or recessed double contact R17d, but they are not very common. Miniature bi-pins are used in T5 linear fluorescents. T9 HID light bulbs use G12 and recessed single contact (R7S RSC) pin bases.
lk_base_g23lk_base_gx23-2lk_base_g24q-2lk_base_gx24q-3
Plug-in compact fluorescent light bulbs are equipped with a two or four-pin base and use a ballast that has been built into the fixture. Plug-in CFLs cannot be interchanged with the ballast; depending on the ballast, only one or two light bulbs will be compatible with the fixture. The two-pin bulbs are for use with magnetic ballasts, and the four-pin bulbs are for use with electronic ballasts. The sockets used in plug-in CFL fixtures are designed to work with only one style of pin base.  This ensures that the correct wattage light bulb is used to match the type of ballast inside the fixture. Some examples of plug-in CFL pin bases are G23, GX23-2, G24Q-2, and GX24Q-3.
lk_base_gu24
Recent energy regulations have spurred the creation of the GU24 base, which has two pins that are 24 mm apart. Only energy-saving CFLs, CCFLs, and LEDs are manufactured with GU24 bases. Incandescent light bulbs are not manufactured with GU24 bases; therefore, a fixture with a GU24 socket will not accept an incandescent light bulb. This guarantees that the fixture is energy efficient.

 

Back to Lighting Knowledge

Comments (0)Add Comment

Write comment

busy