There are two sides to energy-efficient lighting’s story, especially when it comes to dimming CFLs and LEDs.
“Over the last several years, CFLs have become ever more popular, but LEDs are quickly entering the market as the next natural step in the evolution of artificial lighting,” says Jason Sherrill, Marketing Manager for Residential Controls at Cooper Wiring Devices (whose ACCELL product is pictured in action here). “There have been numerous strides made to make these products dimmable; however, when end users pick up a product that’s marked ‘dimmable’ and plug it into just any old dimmer, chances are good that they’ll run into problems. Results can vary from light flickering to turning off early to delays when turned on.”
Despite progress in the field, many CFLs are still not dimmable. And the truth is even dimmable CFLs and LEDs are not terribly effective on their own. While every make of CFL is different — and some are better than others — the newest dimmable bulbs on the market can dim down to 10 percent of maximum intensity. But depending on the specified dimmer or lighting control system, the results vary. LEDs, though fully dimmable in theory, face similar issues.
“People will buy a CFL labeled ‘dimmable,’ and when they try to use it with their regular incandescent controls, the light doesn’t dim all the way down or it flickers or there are other problems,” says Matt Donati, Product Marketing Manager at Lutron.
The solution? Lighting controls must get with the energy-efficient program as well. Fortunately, there are plenty of manufacturers toiling around the clock to make sure dimmable CFLs and LEDs — and compatible lighting controls — work together to meet consumers’ expectations.
The Challenges Involved
Born in an incandescent age, wall dimmers and home lighting controls were made to dim the traditional light bulb using a “triac” to control the brightness. Incandescents operate typically somewhere between 30W and 50W, and the triac needs a load in that range in order to allow an electrical current to heat up the filament to light the bulb.
“[Since] LEDs and CFLs are specifically designed to only dissipate a few watts, this is not enough to keep the triac working properly, and so it switches itself off and essentially switches off the lamp before any dimming can occur, or [at the very least] there is problematic dimming like flickering,” says Paul Wilson, Regional Marketing Director for Lighting and Power Solutions at NXP Semiconductors.
For the most part, the industry has accepted that change — in the form of twists, pins and drivers — is not just coming; it’s here. For manufacturers of lighting controls, that means adjusting their dimming systems to meet the needs of new energy-efficient lighting technologies.
“Like a few other manufacturers, in the beginning, we began testing different CFLs and LEDs on the market to figure out which lamps worked with each of our controls,” says Cheryl Samartano, Product Manager for Residential Lighting Controls at Leviton. “The whole thing was time-consuming and quite inefficient because, right now, there is no standard; every lamp is different. So in the end, we knew we had to come up with a way to get one dimmer to work with all the different lamps on the market.”
Leviton’s solution was the Decora CFL Slide Dimmer, designed for use with a variety of dimmable CFLs. The dimmer detects whether a lamp is an incandescent or a dimmable CFL, determines its best- and worst-case dimming abilities and adjusts its range accordingly. According to Samartano, Leviton tackled CFLs first because they are currently more popular than LEDs. With a CFL solution in place, the company is working on a similar dimmer for LEDs that will address the inconsistencies between drivers.
More manufacturers, including Cooper Wiring Devices and Lutron, are promising big things in the pipeline as well. In the coming months, both companies plan to launch products that will alleviate problems with CFLs and LEDs.
“With the continued growth in choices of dimmable CFLs and LEDs and the associated implications of federal and state legislature, the key for future lighting controls will be functional adaptability,” says Sherrill. “Dimmers offering the flexibility to adjust to the characteristics of any [CFL] ballast or [LED] driver they are connected to will be better aligned to provide an optimal solution.”
Advancements are coming on the lamp side as well. Using its proprietary GreenChip™ technology, NXP recently created an integrated circuit that enables CFL and LED bulbs themselves to be dimmable without any other special technology. The company uses clever circuit techniques to “trick” the triac into detecting that a higher power load is present, allowing it to remain on, even with a low load.
Lighting control companies are a great resource for education and training tools to communicate their products’ improving compatibility with CFLs and LEDs to consumers. For example, Lutron recently launched its LED Control Center of Excellence, featuring training webinars as well as an online LED Compatibility Matrix that explains which Lutron dimmer can be used with LED products currently on the market and the level of performance that results from each combination. Following the launch of its new CFL and LED dimming solution, the company also plans to partner with its top showrooms to get the word out.
“It’s about bringing in bulbs that work well and bringing in products on the control side that are compatible, and talking to customers about why it’s important that all these elements align,” says Donati.