Quick Answer
Calculate CIE Standard Overcast Sky Daylight Factor
Calculator
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Find Engineering Solutions →Result Interpretation
CIE Standard Overcast Sky Daylight Factor calculator computes Daylight Factor in % using the defined engineering formula and the input values provided. Daylight Factor is expressed in %. No universal acceptance threshold is defined by this calculator.
Worked Example
Verified calculation
Given:
- Interior Illuminance = 200
- Exterior Horizontal Illuminance (CIE Overcast) = 5000
Expected Result:
- Daylight Factor = 4
Engineering Interpretation:
Under the given input conditions, the calculated result is: Daylight Factor = 4 %.
The actual numerical result is computed by the Runtime engine using the persisted tool definition. The values shown here come from automatically validated test cases.
Formula / Method
daylight factor = (interior illuminance / CIE Overcast) * 100.0Formula family: formula_lighting_daylight_factor_calculator_cie_standard_overcast_sky
Variables
| Symbol | Label | Role | Description |
|---|---|---|---|
| illuminance_interior | Interior Illuminance | INPUT | Interior Illuminance |
| illuminance_exterior | Exterior Horizontal Illuminance (CIE Overcast) | INPUT | Exterior Horizontal Illuminance (CIE Overcast) |
| daylight_factor | Daylight Factor | OUTPUT | Daylight Factor |
Calculation Steps
- Enter the interior illuminance in lx.
- Enter the exterior horizontal illuminance (cie overcast) in lx.
- Step 1: Compute daylight factor.
- Read the daylight factor (%) from the results.
Engineering Summary
Calculate CIE Standard Overcast Sky Daylight Factor
Frequently Asked Questions
What does this calculator calculate?
The CIE Standard Overcast Sky Daylight Factor calculator estimates Daylight Factor based on the input parameters you provide
Why is interior illuminance important in this calculation?
interior illuminance is directly proportional to daylight factor. When you enter interior illuminance in lx, the calculator uses it in the engineering formula to compute the output
How should I interpret the result daylight factor?
The calculator outputs daylight factor in %. The result is computed directly from the input values using the defined engineering formula
What units should I use for the inputs?
Enter each value in the units shown next to the input field: Interior Illuminance (lx), Exterior Horizontal Illuminance (CIE Overcast) (lx). Make sure all inputs use the specified units for consistent results
What assumptions does this calculator use?
This calculator uses automatically validated engineering formulas. Results are approximate and should be validated against site-specific conditions, applicable codes, and professional engineering judgment
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