Light from LED bulb has long been regarded as too cold to be used in living rooms. But now bulbs come in different colours with a good light projection for all individual preferences. In addition, LED bulbs are even more energy-efficient than energy-saving bulbs. LED bulbs use light-emitting diodes (LEDs) to create light. The principle: A semiconductor crystal transforms flowing electricity directly into light.
What versions are available?
LED bulbs are available for all common types of socket, also for the classic screw thread E27 (conventional bulb) and E14 (candle version). Other types of socket are:
- GU5
- GU10
- GX53
- G9
- GX53
- G4/GU4
- R7
The packaging will tell you which type of socket a bulb is suitable for.
What do the technical terms mean?
Matt or clear with a certain wattage — it’s not as easy to describe the features of an LED bulb as it was with the old bulbs. When making your choice, you should be familiar with the following terms:
- Energy efficiency class: the division into energy consumption classes – from A (most efficient) to G (least efficient).
- Weighted average: The average power consumption, specified for a certain period of time. Example: The specification 2.2 kWh/1000 h indicates that a bulb uses 2.2 kilowatt hours of electricity over an operating time of 1000 hours.
- Rated luminous flux: Rated luminous flux describes the light current escaped from the lamp. The strength is specified in Lumen (lm).
- Colour temperature: Colour temperature specifies the light appearance provided by a source of light in degrees of Kelvin (K). With LED bulbs, colour temperature is usually between 2700 K (warm-white) and 6500 K (cool-white). For people, white light has the optimum composition of the available colour spectra.
- Nominal lifespan: The light intensity of LED bulbs decreases slightly over the course of operating time. The lifespan of an LED bulb describes the time in which the lamp still provides at least 70 percent of its maximum power.
- Beam angle: The angle in which light is emitted from the bulb. Narrow-angled LED bulbs have a higher light intensity for the same light current.
How economical are LED bulbs?
LED bulbs have a very high energy efficiency, even putting energy-saving bulbs in the shade. A conventional 60 W bulb has a light current with a strength of about 600 Lumen. An LED bulb with this luminosity only consumes about 8 W. This contributes to their longer lifespan: An LED bulb can burn for more than 50,000 operating hours.
It is important that the filament allows the electrics to cool down well. Because even if LED bulbs don’t get as hot as conventional bulbs, they create so much heat that they can cause damage over the long term. Aluminium or ceramic heat-sinks are mainly used with LED bulbs.
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