What is the Difference Between A19 and A60?
Light bulbs come in different shapes and sizes. In order to find one that is suitable for your lamp or lighting system, it is important to understand how manufacturers classify such components. One of the most common types of mainstream bulbs is the A19. But there is also the A60, which in some ways is very similar to the A19. This article aims to demystify both types of light bulbs and provide information surrounding universal light bulb codes.
Defining A19 and A60
In order to understand what A19 and A60 means, one must first define the general classification of bulb types. The letter “A” in both titles refers to a standard classification type for general-purpose bulbs in mainstream spaces, such as residential homes. The number that follows after the “A” classification refers to the width of the bulb in one eighth-inch units or millimeters. In the case of A19 bulbs, the unit measures two and three-eighth inches wide and four and three-eighth inches long, with a one-inch long Edison screw base.
A60 is simply the metric measurement version of A19. To arrive at the number 60, one could convert two and three-eighth inches (the widest point of the A19 bulb) to millimeters, which comes out to be 60.45 mm (nominally 60 mm). When it comes to length, the A60 measures 111.25 mm (nominally 110 mm), which is the millimeter equivalent of four and three-eighth inches in length found in the A19 bulb. Both bulbs support the E26 Edison screw base, with A60 measuring at roughly 25.4 mm (nominally 26 mm). One should carefully note that E27 Edison screw base (27 mm diameter) typically found in Australia, New Zealand and the UK is compatible with E26 sockets.
A19 and A60 bulbs support a wide range of commercial applications. Traditionally, they are used in incandescent-type lamps that are prevalent in residential homes, offices and small businesses. The iconic pear-shaped configuration closely resembles generic references of light bulbs. Recently, LED manufacturers released an LED bulb with A19 and A60 specifications. The LED bulbs were ultimately designed to replace incandescent lighting. When installing an LED A19 bulb, there is no need to rewire the fixture. Instead, one could directly replace the outdated bulb by removing it from the socket and installing the LED variant.
The units may also come with other sought after lighting features, such as toggling (mostly associated with LED luminaries) and dimming (depending on the light bulb model). A19 and A60 bulbs may also support different color temperature ratings, including 2,500K for warm, yellowish light and 5,500K for bright light that mimics the conditions of bluish daylight.
Understanding Light Bulb Codes
In addition to the “A” classification, there are other types of categories that can help you quickly determine the compatibility of a bulb with your lamp or lighting system. Some of these classifications include the following:
• B (bullet): Mostly used for decorative purposes
• CA (candle): Found in chandeliers and decorative lighting
• G (globe): Utilized in ornamental fixtures and floodlights
• MR (mirrored reflector): Applied in track lighting systems
• R (reflector): Found in recessed cans, as well as track lighting systems
• T (tubular): A classification for tube lighting, found in industrial and commercial spaces
After locating the respective light bulb code, the corresponding number will indicate the diameter of the unit. In some cases, another letter can be found, which provides information about the length of the bulb. This figure (for example “S” for short and “L” for long) is optional and uncommon.