The lumen (symbol: lm) is the unit of the International System of Units to measure the luminous flux, a measure of the light power emitted by the source. The luminous flux of radiant flux difference that the former provides the variable sensitivity of the eye to different wavelengths of light and the latter involves all electromagnetic radiation emitted by the source according Wien law and Stefan-Boltzmann regardless of whether such radiation is visible or not. 1 lm = 1 cd. sr = 1 lx. m2

VDC would be the abbreviation for Volt Direct Current which translated would volts direct current. The idea of ??this type is unidirectional current to the load. Direct current is normally produced by batteries, thermocouples, solar cells and a dynamo electric machine type. The direct current can flow in conductors such as wires, but may also flow through semiconductors, insulators ... In the image: 1 - current per pulse 2 - Direct Current (DC) 3 - Alternating Current (AC) 4 - Variable Current

VAC would be the abbreviation of Volt Altern Current which would be translated Volts of alternating current. The difference between VDC is that its sinusoidal oscillation achieving a more efficient energy transmission.

The alternating current is the energy that we receive in our homes, it is generated in the power plants by means of alternators.

The intensity of this type of current varies with time, and changes direction 50 times throughsecond (50hz). The generated voltage changes in the form of sine wave so it is not constant.

In the image:

1. Current by pulsations.
2. Direct current (DC).
3. Alternating current (AC).
4. Variable current.

ABS material (acrylonitrile butadiene styrene) is a type of thermoplastic that is very resistant to impact or shock.

Its applications are several, for example is a material widely used in the manufacture of interiors or components of cars such as moldings, as well as in products for domestic use such as toys, tools, housings of electrical devices etc.

One of its most important characteristics is its great tenacidad in almost all types of temperatures.

Being a very hard material has good chemical resistance, low water absorption and high resistance to abrasion, where other types of plastics would be more brittle.

This type of material is becoming very famous in the particular field and widely used due to the great growth in the sales of domestic 3D printers, the main printing raw material.next to the PLA.

Identification of ABS
Parts that are made of ABS material must be marked in accordance with ISO 11469 (DIN 58840).