As light-emitting diode (LED) lighting products continue to proliferate, some LED lighting fixture manufacturers compromise the performance of their fixtures because of industry-wide cooperation aimed at the development of standard specifications for the interfaces of LED light engines.
In many instances, this lack may be attributed to the indiscriminate use of off-the-shelf light engines, the LED module and control gear that convert input power into the necessary power to drive the LEDs.
Ramifications of an off-the-shelf light engine (LE) selection could include unsatisfactory light output, poor lumen per watt performance, and increased assembly time and costs, as well as delivery delays and other problems that can be avoided.
“Off-the-shelf or ‘commodity’ light engines are often perceived by lighting manufacturers to be a standardized product that provides both ready availability and cost savings,” explains Don Bernier, president of Manufacturing and Design Electronics (MADE), an Auburn Hills, Michigan-based LED light engine manufacturer. But, in many cases, lighting manufacturers may be much better off evaluating the use of customized light engines for their fixtures.
Bernier cites several factors that light fixture makers of all sizes should consider before making light engine selections.
Determining True Requirements
Simply because many light engines are produced in high volume doesn’t necessarily make them the best value. Nor should they necessarily be the “standard” for lighting companies.
In many instances, lighting manufacturers are seeking design latitude in terms of sizes, shapes, and mounting hole locations, as well as light output and color temperature that comprise their products.
“Flexibility in fixture dimensions can be problematic when using commodity LEs,” says Bernier. “If a lighting manufacturer has a market for LED fixtures that are longer and wider than usual, they may have to improvise with LE modules in order to power the fixture, and that usually means more costly, time-consuming assembly.”
More important, the finished fixture’s lumens/watt performance or light quality / evenness may be off-target, creating long-term dissatisfaction among end-users.
Conversely, custom light engines are expressly designed and manufactured to fit the lighting output and size requirements of specific lighting fixtures.
“That is accomplished by the light engine design engineers interacting directly with fixture manufacturers on each product, getting an understanding of that project: what their goals are, what the fixture looks like, and lighting output targets,” explains Bernier. “These engineers also determine how many LEDs are optimum, or if a bigger panel is a better solution. Many of these decisions and recommendations can be made fairly quickly once we understand the fixture design and application.”
“At MADE, we take that information, lay out a light engine board, build the board, and then deliver samples to the lighting company for them to test in their fixture. All of this is done efficiently; most of the time, we satisfy the customer’s true requirements with the first samples,” adds Bernier.
Hitting Lighting Targets
When lighting companies simply adopt an available commodity LE, in many instances, it is the same as ignoring the lighting objectives, targets, or the lighting fixture that they are producing.
“Lighting companies should have lumen/watt targets and light output targets for the fixtures they are creating,” Bernier explains. “Once these are determined, the LE manufacturer can make some pretty good assumptions on the efficiency of the light output, the light transfer from the light source to the fixture level. Their experience enables them to develop the right solution so that fixture makers hit their lumen/watt targets and get their certifications and other requirements more easily.”
He adds that too often, the result of settling for a commodity module is finding out that it did not quite hit those targets. This might result in “adaptations,” such as trying an increased drive current, which then may not achieve the lumen/watt goal.
By looking at all of those targets at the fixture design stage, the custom LE manufacturer can usually streamline the light engine design process and find a solution that enables the fixture to perform in the manner that the lighting company desires.
Hitting Cost Targets
Cost is usually a dominant consideration when a light fixture manufacturer selects a light engine module. But, according to Bernier, costs can be misleading.
“The fixture maker usually perceives the possible lower cost of a commodity light engine as a substantial advantage,” Bernier says. “But, in reality, that isn’t necessarily the case. First of all, they are assuming that they couldn’t possibly buy a custom board for a competitive price. Yet, it is entirely possible for a custom light engine company to produce a board for a highly competitive price, perhaps even less expensive. But what if that means—just as with the commodity board—the assembly of the fixture requires wiring two or more boards together? That will increase costs significantly.”
Bernier explains that one of the major advantages of a custom light engine is that it is easier to integrate into the light fixture, requiring fewer connections during assembly, resulting in time and labor savings.
There are other cost options that the custom light engine manufacturer can recommend, such as what type of LED is used for an application. For instance, a properly designed solution might call for more LEDs, but at a significantly lower cost per LED.
Bernier adds that light engine availability is another significant consideration. Lighting manufacturers may run into supply problems when a commodity light engine manufacturer can’t meet delivery requirements because a very large customer has just taken the entire inventory. Smaller, custom LE makers are usually able to minimize delivery problems because they design and plan with their customers ahead of time, which results in consistent, dependable deliveries.
Developing Future Products
Sourcing light engines from a custom manufacturer has another advantage: That is where many lighting technology advancements are developed.
For example, MADE is among the few major light engine manufacturers that are building light engines up to 48 inches long. This advancement in light engine design allows for the quicker, easier, and cheaper assembly of linear light fixtures.
Instead of two, four, or even more light engines wired and connected together to operate a linear or other large LED fixtures, a lighting manufacturer can simply connect the LED lamps to a single circuit board, thereby providing significant savings on labor, components, and assembly time.
Ed Sullivan is a technical writer based in Hermosa Beach, California.