LED light sources have been known to everyone for some time – energy-saving, environmentally friendly and versatile. You still need a little technical jargon to be able to choose the right light body. With such a huge selection of lamp types, it is important nowadays to be at least clear about what terms such as energy efficiency class, lumen and color temperature as well as E27 socket or base stand for. In the next few lines we will deal with this topic of all things and clarify some of the most important aspects of LED light sources especially for you. What are the advantages of LED lamps and why should you replace conventional light bulbs or fluorescent lamps with them??

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Energy consumption and energy efficiency of LEDs

In a nutshell, a lamp should be more efficient to use less electricity. The fact is that LEDs only consume approx. 18% of the energy that is necessary for a conventional light bulb with the same light output. That means: by switching to LED lamps you can save more than 80% in electricity costs! And so it is already clear that LED is currently the more efficient light source, together with energy-saving lamps and compact fluorescent lamps. Less energy consumption automatically means less waste and environmental pollution, so you can enjoy more light with a clear conscience at the same time.

It is not for nothing that all lamps have been marked with the energy label of the European Union (EU) on the packaging since 2014. As with all other electrical appliances, one speaks here of energy efficiency classes. As is well known, these range from A ++, which stands for very efficient, to the worst efficiency class E, which is practically no longer used. A Energy efficiency calculator for lightbulbs immediately gives you the exact efficiency class of a light source. All you need is a few simple details such as power consumption in watts, luminous flux in lumens and lamp type.

Doesn’t that sound a little too complicated? But it is not. Just read on and find out more about it.

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Watts was yesterday, lumen is more important now!

In the past, we only considered the number of watts when we wanted to estimate the brightness of a lightbulb when buying it. The more watts, the brighter the lightbulb was. Since the LEDs entered the lighting scene, the watt value has lost some of its importance. Because only then can we no longer assess the light output of a light source. Lumen is now the name of the value that gives us precise information about brightness. The number of lumens is therefore always on the packaging of a light source next to the efficiency class.

But how should one actually understand the term lumen? Very easily. Lumen (lm) is the standardized unit for the so-called luminous flux or, in other words: for the amount of light that a lamp emits in all directions – the light output of a lamp. Similar to the watt, it also says here – the higher the value, the more powerful the lamp.

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The following gives you a more precise idea of ​​converting watts to lumens:

  • 40 watts = 430 lumens
  • 60 watts = 730 lumens
  • 100 watts = 1380 lumens

For comparison: a candle = about 12 lm

And a simple tip when converting: watts x 10 = lumens (approximately).

In this way you can roughly estimate which LED light source you should buy as a replacement for the old light bulb, if you value the same light output of the lamp. This formula applies above all to the LED lights in the shape of a light bulb.

And then what does light output mean? To put it simply: this term tells you how much of the energy consumed is converted into light. It is not for nothing that the unit of measurement is lumen per watt (lm / W). So, the higher the value, the more powerful / efficient a light source.

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About sockets and bases

Even as a layperson, you probably already know what the socket and base of a light bulb / lamp is. But do you also know exactly what E27 socket means and what is the difference to E14? Again, the answer is much simpler than expected.

The standard for sockets and bases has not changed for LEDs and all other new types of lamps. Just like in the past, E27 and E14 are some of the most common sockets for light sources. In addition, sockets such as GU10 for 230 volts, GU5.3 for 12 volts and GU4 are used very often.

The E27 socket has a typical screw thread, which is often referred to as the “light bulb thread”. The number 27 comes from the fact that the outer diameter of the base is exactly 27 mm. E27 lamps can be found on the market in numerous variants, from LEDs to energy-saving lamps to compact fluorescent lamps. There are also different types available, such as the E27 LED examples from Gluehbirne.de you can see. You can choose between the classic pear shape, spotlight, candle, globe or Edison shape. Usually this socket is used in pendant lights or larger table lamps.

As already guessed, the base of the screw thread of the 14E lamp is smaller than 27E – exactly 14 mm. This version is often very loving too "the smaller sister of E27" called or also “candle holder”. The smaller version is mainly used in desk lamps, refrigerators and chandeliers, but also in sewing machines or extractor hoods.

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Color temperature is still called light color

When choosing the right LED light source, this term plays a crucial role. Because the light color has a direct effect on our well-being and performance by influencing our sleep-wake rhythm, much like the sun does. Warm light has a higher proportion of red light and cold light, on the other hand, has a higher proportion of blue light. While the first promotes the release of melanin in our brain, the second slows it down and you stay awake and focused longer.

You will find LEDs in three color temperatures / light colors – warm white, neutral white and daylight white. Light color is measured in Kelvin. Warm white light is from 2,700 Kelvin and fits best where you should really relax – in the living room and bedroom. Neutral white, on the other hand, starts at 3,300 Kelvin and is more recommended in the kitchen or study. Day white light then starts at 5,300 Kelvin and is used specifically where it is best to concentrate, i.e. at the desk or in the workshop, for example.

Extra tip: The so-called color rendering index (CRI or Ra value) is very important for the actual light quality of LEDs. This should ideally be greater than 90.

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So, if you still haven’t changed your traditional lightbulbs at home or fluorescent lights in your office, it may be high time you did. Think about the brightness and color temperature you want in each individual room and you will find the corresponding value in lumens using comparison tables. Then select the appropriate type of socket / socket and lamp shape and order the desired LED lamps from a well-established manufacturer or dealer on site or online!

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