Glossary of Terms
Colour Temperature
The appearance and ambience created by a light source is referred to as its colour temperature. We call lights ‘warm white’ or ‘cool white’ based on this measure. It is derived from the colour produced when heating a black body. As you raise the temperature the black body produces first a reddish glow, giving way to oranges and yellows, and then finally to blues. These temperatures are measured in the Kelvin (K) scale, with 3000k warm white, 4000K neutral white and 6000k cool white. Oddly, this means the high temperatures of 6000K are called cool and the lower ones of 3000K warm because we associate red with warmth and blue with cool.
CRI
CRI stands for Colour Rendering Index. It’s a test to see how well the light shows colours on a scale of 1 to 100. High CRI gives a more realistic colour appearance so that apples appear properly red and everything looks bright and crisp. Low CRI gives a washed out appearance. Yellow sodium vapour street lights are so bad at showing colour they get a negative rating. A CRI score above 80 is considered more than adequate and is suitable for retail applications. Scores of 90 and above are for specialised museum lighting and medical applications. The overwhelming majority of Haneco lights score 80 or above.
Lumen (lm)
Lumens are a measure of the quantity of visible light emitted. People have grown accustomed to using watts as a measure of brightness, but watts only ever referred to the amount of energy consumed. A 60W bulb is of course brighter than a 40W bulb, but what is being measured is the energy consumed to achieve that brightness. LEDs have so dramatically improved the conversion of power (watts) into visible light (lumens) that a 60W LED emits at least five times as much light as an old 60W incandescent bulb. 800 lumens is roughly equivalent to the light produced by an old 60W bulb, but is the standard output of a 9W LED. And because this level of efficiency is continually improving, it is probably more useful to look at the lumen output of a light rather than its wattage.
Luminous efficacy (lm/W)
Luminous efficacy is a measure of how many lumens are produced per watt. It is just lumen output divided by watts. LEDs typically yield between 70 and 100 lumens per watt compared to 50 for a standard fluorescent and an abysmal 13 to 20 for incandescents. A figure in excess of 100 indicates a highly efficient light.
FAQ's
What are Lumens?
Lumens (lm) are a measure of the visible light produced by a light source. The higher the lumen rating, the brighter it will be. Lumens are a good way to compare LED light output with other light sources. You can find out more about lumens and watts on this page.
I have an existing cutout, will an LED fitting fit?
More often than not, the answer is yes! As LED lighting is often used to retrofit existing lighting, many shapes and sizes have been made to ensure there is one to suit your needs. Several Haneco downlights have adaptor plates that make it possible to put a 90mm cutout downlight into larger holes.
Are LED lights dimmable?
Yes, however their ability to do so is dependent on the driver that the individual fitting uses. Haneco Lighting includes dimmable drivers with most of their downlights, but it is not a standard inclusion on all products.
What is Lux level?
Lux level refers to the intensity of light in a specific space. It is a measure of lumens/m². For example ideal lux levels are 240lux for food preparation, 320lux for offices and 600lux for electronic assembly work. You can find out more about lux and illuminance on this page.