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4.5.5 Daylighting.

This option opens the Tabular Space Data to assign the daylighting parameters for each space as shown below
Daylighting assignment
 
Each daylit area type (Skylit, Primary Sidelit, and Secondary Sidelit) is automatically assigned a daylighting control position, which controls how the space lighting responds to the daylight illuminance measured at the control position. Daylighting in each space utilizes the following inputs:
·        Space ID:  User-defined input for Space ID
·        Space Name: The name of the respective space where daylighting control is assigned
·        Regulated Installed Lighting Power:  This is a reference field which displays the
current regulated installed lighting power for space as defined in previous sections of the navigator.
·        Illum. Set Point: The design illuminance for the daylit area associated with the Daylighting Control Position. Lighting controls are simulated so that the illuminance at the reference position is always maintained at or above the illuminance set point.
·        Daylit Area (Skylit): The skylit daylit area is the portion of the floor area that gets daylighting from a skylight or window.
·        Daylit Area (Primary Sidelit): The primary sidelit daylit area is the portion of the floor area that gets the highest illumination from a window.
·        Daylit Area (Secondary Sidelit): The secondary sidelit daylit area is the portion of the floor area that gets less high, but still useful daylighting from a window.
·        Installed Power: The total lighting power of all luminaires located within the Zone.
·        Controlled Power: The total lighting power controlled by daylighting controls associated with the Daylighting Control Position. By default the checkbox for 100% Controlled is assigned to each space having daylighting control. The user is responsible to uncheck this checkbox and estimate the controlled power below 100%.
·        Ref. Position X,Y,Z : The position of the daylight reference points within the daylit space, identified by the Cartesian X, Y, and Z position of the reference point (feet), with respect to the overall project coordinate system.
·        Daylighting Control Type: The type of control that is used to control the electric lighting in response to daylight available at the reference point.
The options are:
o   Continuous Dimming controls have a fraction to rated power to fraction of rated output that is a linear interpolation of the minimum power fraction at the minimum diming light fraction to rated power (power fraction = 1.0) at full light output
o   Continuous Dimming + Off controls are the same as continuous dimming controls except that these controls can turn all the way off when none of the controlled light output is needed.
o   Stepped Switching Controls vary the electric input power and lighting output power in discrete equally spaced steps. See At each step, the fraction of light output is equal to the fraction of rated power.
·        Minimum Dimming Light Fraction: Minimum light output of controlled lighting when fully dimmed. Minimum light fraction = (Minimum light output) / (Rated light output)
·        Minimum Dimming Power Fraction: The minimum power fraction when controlled lighting is fully dimmed. Minimum power fraction = (Minimum power) / (Full rated power)
·        Minimum Daylit Area:  Area required to be daylit (Skylit plus Primary Sidelit) by Section 140.3c of Title 24 Standards.
·        Skylit. Req. Exception Fraction: The fraction of floor area that is exempt from the Minimum Daylit Area requirement (2013 T-24 Standards Sec.140.3(c)).
·        Excluded Area: Total area that is exempt from the skylight Minimum Daylit Area
requirement.