When you are looking for a light bulb, it is generally broken down into a code. This code comprises of several different parts, explained as follows:
Candle BC 10w
Candle is the shape of the bulb, in this case a candle shape
BC is the type of fitting or connection, in this case a BC or Bayonet Cap
10w is the wattage
Light Fittings/Connections
BC - stands for bayonet cap. This is the traditional fitting that has been around for many years and is widely used throughout the world.
SBC - stands for small bayonet cap. Exactly the same as the normal bayonet cap but smaller.
ES - stands for Edison screw. Also known as screw fittings and is also a very common fitting for older lights.
SES - stands for small Edison screw. Exactly the same as the normal Edison screw fitting only smaller.
GU5.3 - 2 pins 5.3mm apart. Usually used on 12 volt downlighter systems.
Types of light bulb
Whilst there are many different shapes of light bulb available (including golf ball, candle, tube, downlight etc), there are 3 main ways in which light is generated:
CFL - stands for compact flourescant light. These lights currently provide the best balance of efficiency and light (lumens).
LED - stands for light emitting diode. LEDs are the most energy efficient bulbs available however at the moment there are only limited choices
Halogen - The cheapest and most widely available lights today. Whilst slightly more efficient than incandescent bulbs, they still use approximately 70% of the energy of old incandescent bulbs and generate a lot of heat. Halogen bulbs
Incandescent - Traditional lights that emit bright light but use a lot of energy and generally have a shorter life span than the other types of bulb. These types of light have now been banned across Europe due to their low energy efficiency.
Bulb Brightness
Light is measured in lumens. The higher the number the brighter the light. Here is a table showing the different levels from different bulbs:
Bulb Type |
Lumens |
Efficiency (lumens per watt) |
Incandescent (60 watt) |
|
|
Halogen (50 watt) |
|
|
CFL (15 watt) |
|
|
LED (7 watt) |
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