Advice: Guideline to buying LED lighting

40, 60, or 100 watts? E27 or E14? For decades, when buying new light bulbs, consumers only had to make sure that the power was right and that the light source fits into the lamp or the corresponding socket. That was it. The emphasis is on was. Because those times are over since the ban on incandescent lamps in the European Union. The LED has long since established itself as a modern because it is efficient, light source, and is still in the advance. Associated with this, however, are many questions that consumers ask themselves again and again when they stand in front of the shelf: What does all the information on the packaging mean? And how do I find the light source I'm looking for?

We want to try to bring the proverbial light into the dark and therefore explain in this light source guide which information has which meaning. After all, when choosing the right light source, it is no longer enough to just pay attention to the power and the corresponding lamp base.

Power

As with the incandescent lamp, the power of the light source is given in the physical unit of a watt. However, since an LED light source consumes significantly less electricity than an incandescent lamp, the output of the new light sources is of course also lower. As a rule, two different wattages are indicated next to each other on the lamp packaging, the smaller number corresponding to the actual output of the LED lamp and the larger watt number to the comparison value of a light bulb. This should give customers a better orientation when buying and be a small comparison between incandescent lamps and LED lamps.

Luminous flux

Much more decisive than the output in the form of watts is the luminous flux or brightness when buying LED light sources. Both are represented in the physical unit lumen or with the abbreviation lm. The luminous flux indicates the amount of light emitted in all directions by a lamp. The higher the light output per watt, the more efficiently the LED light source works. There can be major differences here. In other words: An LED lamp with a power of 5 watts can, for example, emit more light than an identical LED lamp that is also rated with a power of 5 watts. In other words: the higher the number of lumens, the more light the lamp emits.

Base

For the new LED light source to also fit into the luminaire or the corresponding socket, it must have the correct base. Common screw bases are E27, E14, lamps with the GU10 base are screwed into the socket, and lamps with the GU5.3 or GU4 bases are inserted into the lamp socket.

Light color or color temperature

The light from a floor lamp can be perceived as pleasantly warm or cool and thus have a significant impact on well-being. This is related to the light color or color temperature of a lamp, which is specified in the physical unit Kelvin (K). It can range from warm white (2,500-3,000 Kelvin) to neutral white (3,000-5,300 Kelvin) to daylight white (over 5,300 Kelvin). The consumer must therefore also choose a light source dependent on the area of ​​application and personal taste. The rule of thumb is: The light from an incandescent lamp had a color temperature of around 2,700 Kelvin, which is why most customers in the living area using LED lamps with a warm white light color. Basically, the higher the Kelvin number, the “cooler” the light color.

Lamp life

In contrast to incandescent lamps or halogen lamps, LED lamps to have a significantly longer life, which is specified in hours (unit: h) on almost all lamp packaging. In the case of LED light sources, the lamp life is the average time it takes for the light source to decrease in brightness by around 30 percent.

Dimmability

While halogen and incandescent lamps, for example, can be dimmed relatively easily, it is a bit more complicated with LED lamps. There are more and more LED lamps that can also be dimmed but by no means all. And especially not with every dimmer. That is why the lamp manufacturers usually state on the packaging whether the LED lamp is dimmable or not. A circle with an increasingly wider tail at the top has established itself as a graphic symbol for this.

Color rendering

Depending on the light source, colors can have different effects. This is related to the color rendering of a light source, a quality feature that is indicated by the color rendering index (Ra). Sunlight or the light of an incandescent lamp has the highest possible value with the color rendering index Ra 100. This means that the colors are reproduced in the best possible way in their light. A Ra value of 100 is accordingly the reference or maximum value against which, for example, the LED light sources are measured. The modern light sources with semiconductor technology do not quite reach this value, but almost all light sources nowadays easily reach a Ra value of 80, the high-quality lamps even values ​​of over 90.