The Tunable White fixture’s color is automatically synchronized with the Manage's astronomical clock that provides daily sunrise and sunset times. For this feature to work, you must set the Day and Evening periods of the sensor’s lighting profile to use the astronomical clock. See Periods of a Day and Week Days to set time based on the astronomical clock.
To configure the dual-channel LED of a Tunable White fixture,
- Click Facilities, and select a profile from the Profile Templates navigation tree.
- Click the Settings tab.
- Select the required profile instance and click the Edit button.
In the resulting Edit Profile screen, scroll down until the >>Advanced option is seen and click the >>Advanced option to expand the screen.
The following Dual Channel LED options are provided:
- Circadian Option – When selected, the fixture's color temperature is automatically changed during the day based on the astronomical clock and the selected color temperature settings. The astronomical clock provides the local times for civil twilight (when the sun is six degrees below the horizon, sunrise, solar noon (when the sun is highest in the sky), sunset, and civil twilight at the end of the day. The light color will be changed gradually over time between the settings provided, except at night when it remains constant.
The five circadian periods of the day include:
- Dawn – Transition from night color to sunrise color setting occurs between civil twilight and sunrise.
- Morning – Transition from sunrise color to solar noon color setting occurs between sunrise and solar noon.
- Afternoon – Transition from solar noon color to sunset color setting occurs between solar noon and sunset.
- Dusk – Transition from the sunset color and the night color setting occurs between sunset and end of civil twilight.
- Night -- The night color remains constant from civil twilight at the end of one day until the morning civil twilight before the Dawn transition starts.
Manage provides four-color settings for the five circadian periods of the day. Where 100% is the warmest (2700K) and 0% is the coolest (5000K):
- Sunrise Color Ratio: Set the required % of color transition that has to take place from night color to sunrise color.
- Solar Noon Color Ratio: Set the required % of color transition that has to take place from sunrise color to solar noon color.
- Sunset Color Ratio: Set the required % of color transition that has to take place from solar noon color to sunset color.
- Night Color Ratio: Set the required % of color transition that has to take place from sunset color and the night color.
The color set point format is represented as a direct ratio (0 to 1.0) of the two LED channels T1/T2, where T1 represents the cool CCT LED and T2 represents the warm CCT LED. In the Color Settings, enter a ratio multiple by 100 value.
- T1 = 2700K CCT and the value is ‘0’ percentage value is 0*100 = 0%
- T2 = 5000K CCT and the value is ‘1’ percentage value is 1*100 = 100%
For example: If a Tunable white fixture has a CCT of 3850K
- The range fraction for 2700K is 5000K-2700K = 2300K in comparison to the baseline cool temperature of 5000K.
- The range fraction for 3850K is 5000K-3850K=1150K in comparison to the baseline cool temperature of 5000K.
- The ratio will be 1150K/2300K = 0.5
- Value is 0.5 *100 = 50%.
Note that the fixture's luminance is controlled independently from the color, based on the same methods as non-tunable white fixtures. Also, the location data specified at the installation time must be accurate for color transitions to be supported accurately. To edit location data, see Edit Building's Location Data.
- Understanding Profile Basic Attributes
- Modifying Values of a Profile
- Setting Advanced Attributes when Astronomical Clock is Set