LEDs have been improving exponentially over the past few years. Today, some LEDs last as long as 400,000+ hours; can come with custom Kelvin temperatures, CRIs, and optics; and are the most energy-efficient solutions available.
The LED Difference
One key attribute of LEDs is that they are directional, meaning they send their light in one particular direction. Unlike HID or fluorescent lamps, which throw light in all directions, LEDs are designed to send their light straight out. This makes for less wasted light (within a fixture housing and beyond), higher efficiency, and often allows you to use lower-wattage fixtures for your project.
Since LEDs do not have a filament, they are also more resistant to damage than HID or fluorescent bulbs. LEDs fall into the category of solid-state lighting and hold up well to jarring and bumping. They generate less heat than older technologies and contain no mercury.
What Are LEDs?
A light-emitting diode (LED) is a semiconductor diode that radiates light (electroluminescence) when current passes in a forward direction. Electrons move through a semiconductor and “fall into” other energy levels during their transit of the P-N junction. When these electrons move into a lower energy level, they give off a photon of light. This photon may be in the infrared region or just about anywhere across the visible spectrum up to and into ultraviolet light.
Incorporating LEDs Into Luminaires
Originally, virtually all LED luminaires were made with LEDs mounted directly into a heat sink. They were typically wired in line and went back to a driver. This caused multiple performance issues.
The issue was that the LEDs were usually permanently installed, or at least installed into pre-drilled holes specific to the LED package being used. If an LED failed, it was virtually impossible to fix the fixture. Also, upgrading the LEDs was impossible. There was no effective way to change out all the LEDs.
Current technology has evolved so LED modules are easily replaceable, retrofittable, and customizeable. Fixture housings are being built to enhance the capabilities of LEDs and fixtures are delivering more lumens per watt than ever before.
LED Light Engines/Modules
Nowadays, if an LED module fails, it can be changed just like a light bulb. This allows manufacturers (and eventually, customers) to utilize only the components they want to use.
LED Module Manufacturers
There are many companies that make light modules. Most modules are adaptable, as they come in multiple wattages, have changeable optics, and can be used in a wide variety of luminaires.
LEDs typically do not use standard line voltage. They require transformers, known as drivers, to convert the power to a usable energy supply. This requirement is similar to ballasts used in HID fixtures. There are many manufacturers who make drivers; if you’d like more information on the driver in a specific fixture, contact Access Fixtures today.
LEDs and Glass Lenses
Most luminaires, whether built with older technology or with LEDs, use some form of protective lens. The lens protects the ballast, driver, and light source from dirt and the elements. The optics of a luminaire do not work the same way with different light technologies. Additionally, LEDs have radically different optics than other light sources. The efficacy of the fixture can be reduced by the type of glass or by poor positioning of the LEDs.
IESNA Specified LM-80
The test for lumen depreciation of LEDs is known as IESNA-specified LM-80. The image on this page is an example of the results from this testing. The results shown are for the Xicato LED module used in some Access Fixtures luminaires. Access Fixtures LED luminaires have completed the IESNA-specified LM-80 testing for lumen maintenance at 6,000 hours, with only a 1.8% decrease in lumen output. The test results show the Xicato Modules will maintain 85% of their lumens over 50,000 hours.
Speak to an Access Fixtures Lighting Specialist about Choosing the Right Fixture
Access Fixtures offers standard and custom lighting fixtures that save money and last a long time. With custom manufacturing capabilities, Access Fixtures can build lighting fixtures to the performance specifications you require at a very competitive price. We will be glad to answer your questions. We want to make sure you get the exact fixture for your needs, your budget, and your goals. We are passionate about lighting and love what we do—we’ll get you an answer. To speak with an Access Fixtures lighting specialist, call (800) 468-9925.