Typically, an LED will last four times longer than a CFL and 25 times longer than an incandescent source that puts out the same amount of light.

Unlike discharge lamps, LEDs are semiconductors and their life span is not affected by the number of times they are turned on and off.

The thermal management of the LEDs. If LEDs come on a standalone chip, appropriate heat sinks have to be designed to prevent premature failure of LEDs.The electrical stress: Running LEDs at currents higher than specified make the LED run hot. This can happen with wrongly matched drivers. For example, if the driver produces 700mA but the LED needs 350mA, this will put stress on LED and reduce its l...

Unlike conventional light sources that reduce in output and eventually fail, LED products do not normally suddenly fail. Instead, the light output reduces over time.The normal convention is to measure the life from when the output has reduced by 30%, i.e. when there is 70% light output remaining. This is often quoted as the L70 life and is measured in hours.

50,000 hours would imply 5.7 years if the light is operated for 24 hours in a day, 7.6 years if the lights are on 18 hours per day and 11.4 years for 12 hours a day.

The following are types of optical systems of LEDs:Primary systems with integrated lenses - specific beam angles.Secondary optical systems in the form of lenses, reflectors or diffusers.Combinations of primary and secondary optics for specific applications.

Junction temperature is the LED’s active region; the point at which the diode connects to the base. This is where the electrons jump between the two semiconductors to produce photons. A low junction temperature helps LEDs to produce more light also reduces lumen depreciation. Junction temperature is affected by the driver current, the thermal path, and the ambient temperature.

The two-phase heat technique is a cooling technique that uses the advantages of both active and passive cooling methods.It works on the principle of evaporation and condensation. The process requires disposable heat to initiate the process that happens in a hermitically sealed tube that is filled with a minute quantity of liquid. The system has cooling fins around the tube to dissipate heat. This ...

LEDs are cooled either by passive cooling or active cooling. Passive cooling involves a finned heat exchange system made of cast or extruded metal or a plastic coated metal heat sink that offers a totally silent, robust, heat transfer. Passive cooling is reliant on the surface area of the heat sink material and is orientation dependent. Active cooling may include conventional fans or diaphragm- ba...

Heat management is critical for the performance of LEDs. Increasing heat in LEDs has the following effects in performance characters: Reduction in luminous fluxColor shift (change in color appearance)Reduction in life of the LED

The LED rating of a product is usually noted in milliamps, mA or volts, V. Products rated in mA can be used with a constant current driver, while those rated in volts can be run with a constant voltage driver. LEDs designed for constant current drivers cannot run with constant voltage drivers without damaging them.

Constant voltage drivers are used in applications where the load is not known and the LED loads are connected in parallel, for example in coves and signage applications. These drivers are sometimes similar to the low voltage electronic and magnetic transformers used in halogen light fixtures (MR16 lamps). The type of LED driver suitable to run a LED product is stated by the LED manufacturer in the...

Constant current drivers are typically used in downlights where one, or a series, of luminaires is used per driver. These are connected in series.

LEDs are driven by constant current (350mA, 700mA or 1A) drivers or constant voltage (10V, 12V or 24V) drivers.Constant current drivers fix the current of the system and vary the voltage depending on the load of the LED.Constant voltage drivers require a fixed voltage, and the LED loads are added in parallel across the output of the driver until maximum output currents are reached.

LEDs are low voltage devices. Therefore, they require a device / Power supply unit / driver, or integrated electronics that convert line voltage to low voltage in order to run the LEDs. Sometimes The driver has electronics that can interpret control signals to dim LEDs.

In Europe, every light fitting must have a CE label. This tells you that the seller claims that the fitting conforms to all the relevant European safety standards. The most important of these is EN 60598 which covers electrical, thermal and mechanical safety.

IP (Ingress protection) ratings or UL (Universal Laboratories) ratings are commonly used to determine LED product suitability for various harsh, underwater or outdoor applications.

CELMA is the Federation of National Manufacturers Associations for Luminaires and Electrotechnical components in the European Union. CELMA along with ELC, - (European Lamp Companies Federation) provides standards and guides for LED lighting in Europe.

ANSI (American National Standard Institute) - Establishes definitions of solid state lighting devices and components. It also provides a common terminology.IESNA (Illuminating Engineering Society of North America) - Provides procedures for reproducible measurements of photometry, color and electrical characteristics of solid state lighting products.UL (UnderwritersLaboratories) - Writes safety sta...

Zhaga is an industry-wide consortium aiming to standardize specifications for interfaces between LED luminaires and light engines. The aim is to permit interchangeability between products made by different manufacturers. Zhaga defines test procedures for luminaires and LED light engines so that the luminaire will accept the LED engine.

LEDs are light emitting diodes. These are electronic components that convert electrical energy directly to light through the movement of electrons within the material of the diode. LEDs are important because due to their efficiency and low energy, they are beginning to replace most conventional light sources.

The term solid state lighting is used because the electronics produce light directly from solid materials in which the electrons are embedded. This is unlike other technologies, for example fluorescent technology, which requires agaseous discharge medium to initiate production of light.

LED technology is constantly changing. Rapid innovation continues to improve the performance of LED on an almost daily basis. Future-proofing of LED modules allows luminaire manufacturers to switch from one generation to the next improved generation without major retooling or changes in luminaire design, offering backward compatibility with drivers.

LED chips are mass produced in millions and there are inevitably slight differences in color appearance and light output. Binning is way of sorting the chips so that all the LEDs from one particular bin look the same and have similar light output.

A light engine is the LED equivalent of a conventional lamp. It normally consists of a LED chip mounted on a circuit board that has electrical and mechanical fixings, meaning it is ready to be fixed in the luminaire. Note that the light engine may not consist of only one chip; it may be an array of 9 or 16, sometimes with a phosphor coating.