There are many manufacturers who build excellent luminaires and even more who don’t. By understanding what to look for, quality luminaires can be specified so that projects realize maximum value with minimal headache.
Every light fixture has four parts. These parts are the housing, the LEDs, the power supply (known as a driver) and the optics.
Housing: A properly constructed fixture housing is the foundation of a great luminaire. Fixture housings provide cooling for LEDs and power supplies so it is important that the materials selected offer good thermal conductivity and are built in a manner that allows heat dissipation. Fixture housings for outdoor lights are typically constructed from die-cast aluminum. The exact alloy of aluminum is important, as certain blends of aluminum offer greater durability than others. Outdoor fixtures are typically finished with a baked-on powder-coat finish. The exact type of powder-coat material used is also critical. Low quality powder can have a good initial finish but lacks the longevity provided by superior finishes. At a minimum, powder-coat material should be UV resistant.
LEDs: High quality LEDs offer better electrical efficiency and greater longevity than budget-oriented LEDs. High quality LEDs also provide better light quality and color accuracy. LED performance varies drastically over time between the best and the worst chips. Great LED chips can last well over 100,000 hours with a high degree of color stability. Poor quality LED chips last less than a few years and experience substantial color shift.
Drivers: An LED luminaire’s power supply is called a driver. Drivers are commonly the most expensive part of a luminaire’s bill of materials so many manufacturers cut corners in this department. Drivers have dozens of internal components and electrical connections, all of which need to function perfectly for the system to be reliable. A high quality power supply offers good efficiency and has a broad operating temperature range. To ensure a luminaire is robust, there should be some surge protection built into all outdoor luminaires. Some power supplies offer automatic thermal protection which reduces power levels if a power supply detects abormally high ambient temperatures.
Optics: The design of a luminaire’s optical system can vary significantly by application. The goal of any optical system is to send light to where it is needed. This is achieved through a number of methods including lenses, reflectors, prismatic glass and occasionally through other reflective materials. There are pros and cons to each solution and one is not always superior to another. The main consideration is that an optical system is thoughtfully designed and built with high quality materials. LED chips naturally emit light in a lambertian pattern. A quality optical system will take advantage of this in order to create a smooth, uniform light level on the area being illuminated.
An LED luminaire is only as good as its weakest component.
It is important to recognize that a luminaire is only as good as its weakest system. The greatest optics in the world are not going to perform well if paired with poor quality LEDs. Similarly, long lasting LEDs are not going to matter if the luminaire overheats or if the power supply fails. All aspects need to be considered when designing a luminaire.
Jarvis Lighting wants to support quality lighting installations, whether they use our luminaires or not.
Jarvis Lighting designs and manufactures LED commercial lighting in Elk Grove Village, Illinois. The company’s trademark is “Bright Done Right.” This slogan is our North star. It guides everything we do, from product design to manufacturing to customer service. We’re passionate about high quality lighting systems that offer efficiency, safety and longevity. For more information on Jarvis Lighting, visit www.jarvislighting.com or call us at (800) 363-1075.