Artemide

I Illumination Photometric value showing the quantity of luminous flux for surface area. Com- mon measurement units are lux (lumen / m2) used in the international system, and foot-candle (lumen/ft2) in the United States. Incandescent source Lamp in which the light is produced using an element brought to incandescence by the passage of electric current, which emits radiation in the visible range. Infrared radiation Optical radiation having a wavelength greater than those of visible radiation. Insulating class Homogeneous grouping defined by the IEC (International Electrotechnical Commis- sion), indicating the technical features applicable to an electric device in order to reduce electrical hazards in case of fault. Class I electrical devices: the protection is based on the mains insulation and on a additional security measures. This is made by the connection of the conducting parts accessible to a protection conductor (protection earthing/grounding system) falling under the fixed electrical system. Class II electrical devices: also known as double insulation devices, are manufactured so that the earthing/grounding system is not required. In this case an eventual fault cannot cause the user to come into contact with dangerous electrical tensions. Class III electrical devices: the protection against electrocution is due to the use of SELV (Safety Extra-Low Voltage) security tension. The device is operated either by a battery or by a SELV transformer. International System of Units Abbreviated to  SI system or sometimes just  SI , this is the set of units of measure agreed on by all countries that have signed the Metre Convention. IP International Protection (or protection class IP) is a code summing up the level of protection of an electrical appliance in case of accidental or intentional contact with a human body or with objects, and also the protection against contact with water. IPXX: the first digit shows the protection against the contact with solid bodies and the contact with dangerous parts. The second digit shows the protection against the contact with liquids. Iso-illuminance curve, isolux curve Locus of points belonging to a surface at which the light intensity has the same value.