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May 2017

Lamp Bases in All Shapes and Sizes

On an incandescent light bulb, the component that supplies electrical current is called a “base”. There are several types of foot lamps, and each has a specific application. It is therefore vital to select the light bulb that corresponds to your needs. Indeed, many lamps have their own unique base. This prevents their use in a luminaire that may have a higher wattage, distribute intense heat, and even become a fire hazard. Let’s learn more about lamp bases, which come in all shapes and sizes.

The following infographic explores various components of a light bulb.

Lamp parts

Size Code

The size code is straightforward: a letter identifies the shape or type of base, followed by a digit referring to the cap’s diameter.

The letter “E” means Edison, the inventor of this type of base in the early part of the twentieth century. These lamps have a screw base. They can therefore be screwed on.

Screw bases infographic

The letter “B” stands for bayonet. From an historic standpoint, the shape of this foot lamp resembles the long knife that was once attached to the end of a rifle, thus the name “bayonet”.

Screw bases infographic

The letters “G” and “GU” mean pin cap. The letters “GU” suggest that this specific lamp is equipped with a component supported by the luminaire. Initially, these lamps were made of glass, which is why the letter “G” has been kept.

Screw base infographic

LED Equivalency Guide

After many years of refinement, LED lamps have finally achieved their objective: offer an economical and efficient substitute for the conventional light bulb. LED lamps have a longer life span (over 20 years), they produce a fine quality light and are quite solid. In many cases, these lamps are made of plastic as opposed to glass.

Marketplace competition has brought a significant drop in the price of LED lamps and, by the same token, a serious improvement in lamp design. This trend has led to the development of LED-based alternate solutions that encompass a whole range of multiple use luminaires.

To facilitate the transition to LED lighting, the screw base size codes and the size of light bulbs remains the same.