Average illuminance (Eav)=Total luminous flux of light source (N*Ф)*Utilization factor(CU)*Maintenance factor(MF)/
Area area (㎡) (suitable for indoor or stadium lighting calculations).
Utilization coefficient: generally indoors take 0.4, sports take 0.3.
Maintenance coefficient: generally take 0.7 to 0.8.
Example:
(1) Indoor lighting: 9 sets of 3×36W grille lights are used for a 4×5 meter room.
Average illuminance=total luminous flux of light source×CU×MF/area=(2500×3×9)×0.4×0.8÷4÷5
=1080
Lux
(2) Gymnasium lighting: 20 × 40 meters, using POWRSPOT
60 sets of 1000W metal halide lamps,
Average illuminance=total luminous flux of light source×CU×MF/area=(105000×60)×0.3×0.8÷20÷40
=1890
Lux
Extended information:
The standard value of illuminance is 0.5, 1, 3, 5, 10, 15, 20, 30, 50, 75, 100, 150,
200, 300, 500, 750, 1000, 1500, 2000, 3000
, 5000lx
Grading. lx (lux) is the unit of illuminance.
The illuminance standard value classification is based on the subjective effect of obviously feeling the smallest change in illuminance, and the illuminance difference is about 1.5 times.
Under direct sunlight in summer, the light intensity can reach 60,000 to 100,000 lx, 10,000 to 10,000 lx outdoors without the sun, 100 to 550 lx indoors in bright summer, and 0.2 lx under the full moon at night.
Incandescent lamps emit about 12.56 per watt
lx light, but the value varies with the size of the bulb, a small bulb can emit more lumens, and a large bulb has less. The luminous efficiency of fluorescent lamps is 3 to 4 times that of incandescent lamps, and the lifespan is 9 times that of incandescent lamps, but the price is higher.
