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What does E27 mean?

E27 means a thread with a diameter of 27 millimeters, and it is one of the most common sizes of Edison thread used for lighting purposes. The letter“E” refers to Edison, the inventor of the light bulb and the screw thread.

The origin of the Edison screw thread

In the late 19th century, Thomas Edison developed the light bulb, a revolutionary invention that forever changed the way we create and distribute light. But the light bulb was not Edison’s only invention that would influence the lighting industry. One of Edison’s other important inventions was the screw thread that held the light bulb in place: the Edison screw thread.

Mass production possible

The invention of the Edison screw thread made it possible to produce and sell light bulbs on a large scale. Thread standardization made it easier for manufacturers to market their products. In fact, they knew that their light bulbs would fit into any socket with an Edison thread. This created tremendous growth in the lighting industry. As a result, the light bulb became more affordable to the masses.

What does E27 mean?

The Edison thread is designed for easy and safe insertion and replacement of incandescent bulbs in the fittings. The thread has a standard size that is denoted by the letter E followed by a number. The number refers to the diameter of the thread in millimeters. The most common Edison thread sizes are E27 and E14. E27 refers to a thread diameter of 27 millimeters and E14 refers to a diameter of 14 millimeters.

How are we doing these days?

Although incandescent bulbs have since been replaced by more energy-efficient alternatives, the Edison thread is still used. LED bulbs and halogen lamps often come with an Edison threaded fitting. This makes it easier for consumers to replace their old incandescent bulbs without having to change the socket.

So the Edison thread remains an important standard in the lighting industry. A standard with a rich history and a lasting impact on how we create and experience light.

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