When someone not in the lighting or electrical industries begins to try to research different types of lights and possible upgrades, it is often a very daunting task.
This is often not only due to the rapidly changing technologies in lighting today, but also due to the industry jargon that is often used and the alphabet soup that represents it.
First, some background about why all of these terms are even necessary. The primary reason for most of these different sets of letters and numbers is to enable those in the industry to quickly identify and understand different types of lights, as well as sizes and dimensions and ways they connect together.
Most letter and number combinations refer to an abbreviated description that is somehow associated with how the light works or connects to the socket, and the numbers typically refer to a measurement associated with the specific light or its connection. Some aspects are relatively standard across the industry, such as the number typically referring to the diameter of some aspect of the lamp / bulb / connection. As a quick reference here are a few of the most common:
E26 (Also E27) - This is listed first since it is related to Thomas Edison - often thought of as the father of the light bulb due to his invention of the traditional incandescent bulb. The "E" stands for Edison and refers to the common threaded metal base that screws into a light socket like those found on a household, incandescent bulb. The number following the "E," as one might expect from the brief description above, refers to how many millimeters in diameter the screw-in base is for the particular bulb.
MR16 - MR refers to Multi-faceted Reflector - this is a bulb that has a bipin (2 pin) base. The number refers to the number of eighths of an inch (1/8") across the diameter of the face of the bulb.
PAR 38 - Refers to a Parabolic Aluminized Reflector (PAR) lamp that is 4 3/4" (38 / 8 inches) in diameter. These lamps are characterized by having the lamp, lens and reflector all sealed together in the same unit. They typically have relatively poor directional control of where the light is being projected (soft edges).
T-8 - This refers to a tubular light that is one inch in diameter. The "T" stands for tubular and the 8 refers to the number of eighths of an inch and is a common size of fluorescent tube.
GU10 - Refers to another type of bi-pin (2-pin) code. The G stands for glass and GU often refers to a twist-lock feature of the bulb. The number defines the distance between the centers of the pins measured in millimeters. The center is used because the pin often has two diameters, with the larger used to facilitate the twist and lock feature.
As mentioned earlier, this is only a few of the most common codes used in the lighting industry, but hopefully they are a helpful start. To learn more about common LED lighting terms, check-out our FAQ section or our list of industry terms. As always, let us know if you have questions or comments using the comment section or our contact page. Or register in our guest register to receive periodic updates or topics of interest.