Important knowledge of lighting

15/09/2021
IP Protection Ability
Ingress Protection is the abbreviation of Ingress Protection, the code used to determine the protection level of lamps and lanterns internationally. The IP level is composed of two numbers to indicate the waterproof and dustproof level of the lamp. The first number indicates the protection ability of the lamp against people, solid foreign objects or dust; the second number indicates the protection ability of the lamp against water, the larger the number indicates the lamp The better the protection performance.



Light intensity distribution curve
The light intensity distribution curve is also called the light distribution curve. On the plane passing through the center of light, the luminous intensity
of the light source or illuminator in each direction in space is expressed as a curve of the angle (calculated from a given direction) function, expressed
in polar coordinates or rectangular coordinates.
Its main uses are:
1. Provide a general concept of light distribution characteristics of lamps
2. Calculate the illuminance generated by the lamp at a certain point
3. Calculate the brightness distribution of the lamps

Luminous flux
The derived amount of radiant flux evaluated according to the standard human visual characteristics of international regulations, the symbol is ΦV or Φ, and the unit is lumens (lm).

Illuminance(E)
The illuminance of a point on the surface is equal to the quotient of the luminous flux irradiated on the surface element containing this point and the area
of the surface element, the symbol is E or Ev, and the unit is lux (lx).

CCT
Color temperature (unit: K) is the color change that human eyes can perceive under different energies of light waves. Take the flame as an example. The central flame with the highest temperature is blue, the middle is yellow and white, and the outer flame with the lowest temperature is orange-red. It can be seen that the colors corresponding to the low color temperature to the high color temperature are orange-red, white, and blue.


Color rendering index(CRI)
A parameter that measures the ability of a light source to present the true color of the illuminated object. The higher the color rendering index (0~100) the light source is closer to the natural color.

Selection of electricity shocking-proof grade
For electrical safety, all live parts of lamps must be isolated by insulator materials. This protective measure for personal safety of lamps is called anti-shock protection. According to the method of anti-shock protection adopted by lamps, lamps can be divided into I, II, III Three categories.
Lamp grade Main performance of lamps Application note
Class I In addition to the basic insulation, the accessible parts
and the shell have grounding devices, once the basic
insulation fails, there is no danger.
Used for metal shell lamps, such as flood lights,
street lights, garden lights, etc., to improve safety.
Class II In addition to basic insulation, there is supplementary
insulation, which can be made into double insulation
or reinforced insulation to improve safety.
Good insulation, high safety, suitable for lamps with
poor environment and frequent touch by people,
such as desk lamps, portable lamps, etc.
Class III Use extra low safety voltage (AC effective value is
less than 50V), and no voltage higher than this value
will be generated in the lamp.
The lamp has the highest degree of safety and is
used in harsh environments, such as machine tool
work, children's lamps, etc.