An average rating, in hours, indicating when a percentage of a large group of lamps have failed, when operated at nominal lamp voltage and current. The life of an LED is defined as the operating time in hours for the lamp to reach L70 which designates 70% lumen maintenance (or 30% reduction in initial light output). Every lamp type has a unique mortality curve that depicts its average rated life.
Refers to the luminous intensity at the center of the beam of a blown or pressed reflector lamp (such as a PAR lamp). Measured in candelas.
A two-terminal semiconductor device having a p-n (positive-negative) junction which allows energy travel in one direction.
A self-contained power supply that has outputs which match the electrical characteristics of the lamp. It is similar to a ballast and is used to power illumination sources.
A footcandle is one lumen per square foot. The 16th General Conference on Weights an Measures (CGPM), Oct. 1979, decided that the candela is the luminous intensity of a source emitting monochromatic radiation of frequency 540 x 1012 Hz and radiant intensity 1/683 watt per steradian. This corresponds to 683 lumens per watt of radiation at approximately 555 nm wavelength, which is near the maximum of the standard photopic spectral luminous efficiency curve.
A heat sink is an environment or object that absorbs and dissipates heat from another object. The design of an LED retrofit lamp's heat sink is an integral factor in the overall performance of the lamp.
LEDs are made from very thin layers of semiconductor material; one layer will have an excess of electrons (the n-layer), while the next will have a deficit of electrons (the p-layer). This difference causes electrons to move from one layer to another, thereby generating light. The process of making LEDs is very intricate, with hundreds of steps.
LED technology offers many environmental benefits. The production and use of LEDs requires significantly less energy than incandescents or CFLs. With Illumitex LED Lighting products, there are no lamps to throw away and the entire fixture is recyclable with no mercury content to worry about. All Illumitex LED Lighting products are free of mercury and other toxic materials, a clear win for the environment.
A full evaluation of LED products requires a review of the overall system efficiency, optical control, thermal management of the LEDs, and an assessment of the point in time the fixture will reach 30 percent lumen depreciation. Products with good optical efficiency and thermal management will be able to deliver more lumens, on average, than traditional HID products as well as other, poorly designed LED lighting products. You asked a good question; it's important to thoroughly evaluate LED products before buying.
Illumitex LED fixtures are designed with maximum LED diode junction temperature and proper thermal management solutions in mind. These products are robust enough to operate in typical and ambient environments. Our LED efficiency is well demonstrated.
Unlike other light sources, LEDs don't suddenly "burn out;" instead, the diodes gradually produce lower light levels over time. LED useful life is generally based on the number of operating hours until the LED is emitting 70% of its initial light output (known as L70). All of Illumitex's LEDs are rated to at least 50,000 hours at L70 in a 25° C ambient environment, with some fixtures offering much longer lifespans and even higher ambient temperature environments. LED light output and useful life are strongly affected by elevated temperature due to improper design of the thermal management system. So how long do LEDs last? Illumitex LEDs last a long time.
While incandescent and fluorescent lighting will fail sooner when switched on and off often, LED lighting is unaffected by how often it is turned on and off.
The IP stands for Ingress (the act of entering) Protection. The first numerical digit describes the rating that is given for solid objects. The 6 here is the highest rating and means the LED is dust tight. The second numerical digit defines how well the LED can keep liquid out. On a scale of 1-8, 6 is pretty high, meaning Illumitex's IP66-rated LEDs are very water tight and suitable for installations where they're likely to be sprayed by water, such as horticultural and agricultural applications.
Lumen (lm) is a measure of luminous flux or quantity of light emitted by a source.
A lux is one lumen per square meter; differs from foot-candle by about a factor of 10.