Cases/FAQ

[Illumination FAQ] Vol.3 How to choose a bulb? It’s all about the last 2 numbers!!

Hi, everyone. Former 2 volume (and 1 special volume) we introduced the basic technical detail about lights. After that, we’re going to talk about the installing mount of lights. This topic will be divide into 2 parts. Bulb will be the first part, and tubes will be second. Hope this one can help you, while you’re picking lights in market.

Let’s begin!!

First, we are going to discuss about E27 bulb.

E27 holder

E27 holder means the spiral holder under the bulb. E represents the renowned inventor, Tomas Edison. E series was invented by him in 1909.

#The last emperor of China, Pu-Yi, just succeeded.

Graph 1. E27 Bulb, the last emperor, Tomas Edison

Graph 2. E24, E14, E10

Last 2 digit stand for spiral diameter. For example, 27 means 27mm.

There are many different holders in E series. E12 is a commonly seen holder in our daily life. Usually used to replace candle.

Traditional street lights usually use E40. However, they are mostly replaced by integrated LED lights lately. Spiral holders are not used 

Graph 3. LED Street light

About next episode:

After a brief topic about bulb, we are going to talk about tube next time.

Hope you can enjoy it. See you next time!