Specialized news in lighting

1.What is Power Consumption?

In electrical engineering, power consumption refers to the electrical energy per unit time, supplied to operate something, such as a home appliance. Power consumption is usually measured in units of watts (W) or kilowatts (kW).

2. What is Luminous Xlux?

In photometry, luminous flux or luminous power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of electromagnetic radiation (including infrared, ultraviolet, and visible light), in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.


3. What is Luminous Efficacy?

Luminous efficacy is a measurement commonly used in the lighting industry that indicates the ability of a light source to emit visible light using a given amount of power. It is a ratio of the visible energy emitted to the power that goes into the bulb from the electrical line (visible energy emitted is also known as luminous flux, and the units are measured in lumens). Note: in some countries, luminous efficiency is substituted for luminous efficacy. Luminous efficiency, however, is a unitless measure (watts out / watts in) where luminous efficacy is not (lumens out / watts in).

4. What is the performance of light?

• A measure of the efficiency of a light source in lumens per watt (LPW).

• Determine the amount of light emitted when consuming one Watt of electrical energy.

• Symbols: η (Greek letter, pronounced ether).

• Unit: lm / W (lumen / Watt).

• It is a parameter showing the quality and energy saving of lights.

5. Light intensity:

• Light intensity (I): The flux of a light source emitted in a unit of spatial angle.

• Candela unit, symbol cd.

• A single candela will emit 1 lumen over an area of ​​1 square meter at a distance of one meter from the center of the light source.

6. What is glare?

• Luminance (L): The intensity of an extended diffuse light source or an object that reflects light.

• Is a characteristic quantity for the density of light intensity distribution I on a surface area S in a given direction.

• 1nit = 1cd / 1m2

7. What is the reflectance (ρ)?

• The reflectance of an object is the quantity measured by the ratio of the reflected luminous flux (Φr) of the object to its incident luminous flux (Φ).

• ρ=Φr/Φ

8. What is illuminance?

• Illuminance (E): The typical quantity of light flux per unit area.

• Lux unit, symbol lx

• 1lux = 1lm / 1m2

• Illuminance is the brightness received on the illuminated surface.

• Illuminance relates to the position of the illuminated face.

• When calculating the lighting design, it is required to have illuminance according to state standards.

• Usually on light bulb product packages, an average illuminance is used, or the illuminance index is accompanied by a distance to the light source.

9. What is color temperature?

• Color temperature (K): The color of the light emitted by the light source, unit Kelvin.

• A substance begins to emit red light at 1000 degrees K, becomes white at 5000 ° K and turns green at higher temperatures.

10. What is the color rendering factor?

• Color rendering index (color rendering index)

• A measure of the degree of fidelity of the color of the space and objects illuminated in the light of the bulb compared to the natural light of the sun.

• Color rendition is represented by an index (CRI) of magnitude from 0 to 100.

11. Absorption coefficient (α):

• The absorbance coefficient of an object is a measure of the ratio of the absorbed flux (Φa) of the object to its incident luminous flux (Φ).

• α= Φa/ Φ

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