Color Temperature
Correlated Color Temperature (CCT), refers to the color appearance or the look and feel of the light source. The cooler or crisper the appearance of a light source means the higher the CCT measured in Kelvin (K). Many Appleton LED luminaires offer more than one color temperature.
• Three color temperatures to suit customer preference
• Preferences shift from blue-rich, 5000K CCTs to warmer values
— Bluish-White = K
— Yellowish-White = K
Guide to Using CCT
| COLOR TEMPRATURE | WARM WHITE | NEUTRAL | COOL WHITE |
|---|---|---|---|
| Kelvin | 3000K | 4000K | 5000K |
| Mood & Effects | Soft, Warm, Pleasing | Neat, Clean, Efficient | Bright, Alert |
| Typical Applications | Interior, Fog, Dark Sky or Wildlife Friendly | Low Mounting Heights, Warehouse | Reading, Highlighting Details Dust |
Selecting the Right Lumen Level
Because LED luminaires are more efficient than their HID predecessors, a watt for watt replacement would yield significantly higher than desired light levels. Generally, an LED equivalent luminaire produces the same light with 1/3 to 1/2 the energy consumption of HID. To the right is a guideline of the total LED luminaire output needed to effectively replace an HID luminaire. Since mounting height, luminaire beam pattern, and overall lighting conditions can all affect perceived illuminance levels, it is always best to request a lighting simulation and a luminaire sample. Contact an AppletonTM representative for more information.
A Word About Perceived Brightness
The human eye has two types of photoreceptors: cones, which are active in brighter light levels, and rods, which take over in darker conditions. Commercial photometry measurements are based on photopic luminous efficiency, which only involves the cones. However, recent research shows that a white light source is perceptually and functionally brighter than its High Intensity Discharge (HID) equivalent, especially in a dimly lit application, due to the difference in the spectral power distribution of these light sources. Unfortunately, no universal standard exists today to convert traditional HID measurements to their LED counterparts.
| HD EQUIVALANT | LED LUMEN RANGE |
|---|---|
| 70 Watt | 2000 - 3000 |
| 100 Watt | 3000 - 4000 |
| 150 Watt | 4000 - 5000 |
| 175 Watt | 5500 - 7000 |
| 250 Watt | 8000 - 10000 |
| 350 Watt | 10000 - 12000 |
| 400 Watt | 12000 - 14000 |
| 600 Watt | 16000 - 18000 |
| 750 Watt | 18000 - 20000 |
| 1000 Watt | 24000 - 26000 |
| 1250 Watt | 29000 - 31000 |
| 1500 Watt | 37000 - 39000 |