The technology indicates the operating base of a light source. The most well-known and energy-efficient example is LED. Other techniques include Halogen, gas discharge, TL (fluorescent) and the light bulb.
Cap / Base
The cap/base of a bulb is the part that connects it to the socket in the fixture. In Ireland, B22 (Bayonet) caps/bases are still the most popular, although E27 (Edison screw) caps/bases are becoming increasingly popular. GU10 is the most common cap/base for spotlights. Check which cap/base you need carefully as many other types are also available.
The wattage indicates how much energy a light source consumes. With LED lighting, the wattage is considerably lower than with conventional lighting. LED lamps with a higher wattage generally also have a higher light intensity (number of lumens).
Colour temperature (Kelvin)
Light colour is also known as colour temperature and is expressed in Kelvin (K). You can choose from:
Extra warm white (1700K - 2700K). Atmospheric light. For places with a relaxing character.
Warm white (>2800K). Neutral and soft light. For common areas such as halls, corridors, foyers.
Cool white (>3400K). Fresh and natural light. Good for focus/concentration in schools and offices
Daylight white (>5000K). Equals natural daylight. Suitable for situations where a lot of light is needed.
The colour code is a combination of colour rendering (CRI) and light colour (Kelvin). The first number indicates the colour rendering (1 = very poor colour rendering, 9 = maximum colour fastness). The second and third number contains the light colour. Example: the colour code 830 consists of good colour rendering (8) and warm white light (3000K).
Dimmable bulbs work in combination with a dimmer switch and allow you to determine the desired light output. Dimming also provides energy saving potential because less power is required when the lamp is producing less light.
Light Output (Lumen)
The number of lumens (lm) is the light output of a light source. The higher the number of lumens, the more light the light source emits. The wattage and the number of lumens are not connected to each other. An LED lamp with a low wattage can have a higher number of lumens than a conventional lamp with a high wattage.
Lighting with a voltage of 220-240 Volt can be connected directly to the mains. Lighting with a different mains voltage (12 Volt and 24 Volt) requires an (electronic) transformer.