By Paul Abelson
senior technical editor
LEDs are producing more light, all the while getting cheaper and lasting longer. What more could you want out of a light?
In 1990, when the folks at Grote introduced the first lamp lit by a light-emitting diode, little did they realize they were starting a revolution that continues to this day.
The next year, Truck-Lite adapted LEDs for use in stop/tail/turn lamps. LEDs have been used for taillamps and exterior lamps for a while and now truck builders are finding more and more places to use them inside the sleeper and all over the cab.
And why not? There are not many products today that are getting cheaper while performing better and lasting longer.
Early diodes were quite weak, especially when compared with the output of today’s diodes. For example, Truck-Lite’s first stop/tail/turn lamp had 63 diodes, compared with only six in their current 4-inch round lamp.
What makes the incredible progress in LED lighting a reality is that with superior materials and optic designs, technology is wringing more light out of every watt. And those newer, more efficient diodes are becoming available on a regular basis.
Who is Roland Haitz?
LEDs started with fewer than 5 lumens per watt, requiring many diodes. Roland Haitz, a researcher at diode maker Hewlett-Packard, predicted that the rapid technological advancements – and the decline in cost – would happen. The concept now carries his name: Haitz’s Law.
Output is now about 70 lumens and is projected to reach between 180 and 200 by 2020, according to U.S. Department of Energy studies. Both Grote and Truck-Lite have single-diode lamps in their catalogs.
LEDs are also more efficient than their incandescent counterparts. A 4-inch round stop lamp with an incandescent bulb uses about 2.1 amps to meet lighting requirements of Federal Motor Vehicle Safety Standard 108. Using LEDs, the same requirements are met with only 0.5 amps.
On a total lifecycle cost basis, you can’t beat LED lighting. That’s why approximately two-thirds of all new trailers and almost as many tractors are delivered with LED lighting. At a growing number of manufacturers, LEDs are standard.
Also comes in white
White LEDs are the newest frontier of lighting. Several years ago, the Truck-Lite folks pioneered backup lamps and interior lighting for trailers. White LEDs offer the same low current consumption and long life inside as they do outside.
Using proprietary optics, manufacturers are developing LED cab and sleeper lighting. LEDs reduce battery drain with engines off, saving them for climate control.
White LEDs excel at forward and auxiliary lighting. Besides license plate and back-up lamps, Truck-Lite and Grote developed work lamps. Proprietary optics shape the light to suit requirements.
Grote pioneered auxiliary forward lighting using LEDs with its Trilliant LED White Light work lamp, tested as auxiliary forward lighting in the 2006 Baja 1000 off-road race. Grote’s “ergonomic lighting” approach optimizes rather than maximizes light output for the tasks for which it is used.
Peterson Manufacturing employed the white diode technology to design a brilliant traveling companion for its Piranha-brand LED family. Peterson calls it the “Great White.” American SuperLite calls its white LED product the “White Dragon.”
Truck-Lite recently introduced a 7-inch round replacement LED headlight, currently made in a 24-volt version for the U.S. Armed Forces. It has seen service in several up-armored vehicles, including the new mine-resistant MRAP truck.
While standard halogen headlamps have a 400-hour design life, Truck-Lite’s LED headlight is expected to exceed that by 50 times.
Army tests indicate the headlamps may last the full 20 to 30 years of life that is standard for military vehicles. A 12-volt version for civilian Class 8 heavy-duty trucks was unveiled this fall.
Focus on the future
Imagine having lamps that provide optimal lighting for every task and need. Imagine wiring that won’t corrode or cause shorts that burn out bulbs. Imagine never having to replace a lamp or bulb again.
These things are not that difficult to imagine, because they’re here now. And with Haitz’s Law firmly in effect, these new technologies will soon be far more affordable. LL
Paul Abelson can be reached at firstname.lastname@example.org.