Ingress Protection Ranking (IP Ranking)

Ingress Protection (IP) ratings are developed by the European Committee for Electro Technical Standardization (CENELEC)
(NEMA IEC 60529 Degrees of Protection Provided by Enclosures - IP Code), specifying the environmental protection the enclosure provides.

The IP rating normally has two numbers:
1. Protection from solid objects or materials
2. Protection from liquids (water)

Example - IP Rating
With the IP rating IP 54, 5 describes the level of protection from solid objects and 4 describes the level of protection from liquids.
An "X" can used for one of the digits if there is only one class of protection, i.e.
IPX1 which addresses protection against vertically falling drops of water e.g. condensation..

IP First number - Protection against solid objects
0 No special protection
1 Protected against solid objects up to 50 mm, e.g. accidental touch by persons hands.
2 Protected against solid objects up to 12 mm, e.g. persons fingers.
3 Protected against solid objects over 2.5 mm (tools and wires).
4 Protected against solid objects over 1 mm (tools, wires, and small wires).
5 Protected against dust limited ingress (no harmful deposit).
6 Totally protected against dust.

IP Second number - Protection against liquids
0 No protection.
1 Protection against vertically falling drops of water e.g. condensation.
2 Protection against direct sprays of water up to 15o from the vertical.
3 Protected against direct sprays of water up to 60o from the vertical.
4 Protection against water sprayed from all directions - limited ingress permitted.
5 Protected against low pressure jets of water from all directions - limited ingress.
6 Protected against temporary flooding of water, e.g. for use on ship decks - limited ingress permitted.
7 Protected against the effect of immersion between 15 cm and 1 m.
8 Protects against long periods of immersion under pressure.

Light Spectrum

Spectrum is double color after spectral dispersion system by dispersion of monochromatic light according to the size of the
wavelength (or frequency) sequential pattern, called the optical spectrum. Is the largest part of the visible spectrum in spectrum
electromagnetic spectrum in the visible part of the human eye, in this wavelength range of electromagnetic radiation called
visible light. Spectrum does not contain visual can distinguish all the colors of the human brain, such as brown and pink.
 
Light waves are generated by atoms internal movement of electrons. The inner electrons of atoms of each substance in the
movement, so the light waves, they are also different. The glow and absorb light of different materials in the study, have
important theoretical and practical significance, has become a specialized subject, spectroscopy.