The benefits of light-emitting diodes (LEDs) for exteriorlighting on commercial vehicles are fairly well established: superiorbrightness compared to incandescents and shock-resistant diodes with extremelylong life, resulting in lower maintenance costs. While the upfront cost of LEDsis still greater than for comparable incandescent lamps, the overall cost ofownership can be much less, with the possibility that LEDs will last the lifeof a vehicle, even if that is the ten-year life-span increasingly expected of atrailer. However, LED lighting is not maintenance-free: the whole lightingsystem –– lamps, harness, connectors –– require proper care to fully realizethe long life LEDs can achieve.
Today’s tight economy further emphasizes the need forcontrolling costs and reducing maintenance. With that in mind, we asked somemajor LED lighting manufacturers for their recommendations on maximizinglighting performance.
The right spec
“Good spec’ing, good maintenance and eliminating badpractices that cause problems are three big things you can do to mitigate yourtotal lighting costs,” says Brad Van Riper, Truck-Lite Inc.’s senior vicepresident and chief technology officer. He advises that a fleet buying lightingshould consider LED products. “There’s so much success reducing lightingmaintenance with LEDs that they are no longer thought of as a consumable,” VanRiper explains. If you have a good specification, LEDs should last the life ofthe vehicle. “The technology is there, and if you buy from a reputablesupplier, you should have that kind of performance.”
New products offer a number of improvements, he notes, suchas having significantly fewer diodes, which lowers cost, while maintainingprevious illumination levels. As an example, Van Riper says Truck-Lite’s whiteLED round back-up light Model 44 offers the same performance with six diodesthat used to take 60. The reduced number of LEDs significantly lowers the cost.Fleets that have thought LEDs were too expensive should note that improvementshave occurred and prices have come down, so are worth another look if one isconsidering replacing incandescent lights. A small increase in upfront cost canreduce long-term costs, Van Riper notes. Another advantage is reduction ininventory costs, since a fleet won’t have to stock and track as manyreplacement bulbs. “Look at what’s in your parts bins; you might want toconsider a transition program to get away from incandescent products,” hesuggests.
There are also recent additions to the applications for LEDlighting, such as Truck-Lite’s work light line, featuring new shapes and higherlight output. Fleets that haul tankers and bulk dry products are finding thesework lights especially helpful in illuminating the manifolds used to offloadtheir product, according to Van Riper. The work lights are now finding theirway onto other vehicles that fleets often have the responsibility to maintain,such as forklifts, where LEDs’ shock-resistance and utility in darkenedwarehouses are valued.
“LEDs represent a greater expense up front, maybe a fewhundred dollars, but you’ve got to look at the overall cost of ownership,” saysPage Large, Grote Industries’ national fleet sales manager. “Over the totallife of the asset, LEDs make sense.” He also stresses that LED lighting canhave a safety and performance benefit, because it appears brighter thanincandescent and offers instant on/off illumination. Large notes that somefleets are using dual-intensity LED marker lamps on their trailers’ upper railto serve as a high-mount stop light –– similar to the one passenger cars havehad for years –– to signal when the truck is turning or braking. “The lampshave to be up there anyway, so you might as well get more bang for the buck andmake them dual-intensity auxiliary stop or turn lamps,” he says. “It’s veryeffective, it’s logical, and it typically costs less than $100 per vehicle.”
Another advantage of LEDs, according to Large: because theydraw about a fifth less amperage than incandescents on a typical 53-ft. dry vanlighting package, LEDs leave more amps for other current draws being added totrailers, such as tracking devices, lift axle systems, tire pressure monitors,and the like.
Tim Gilbert, Peterson Manufacturing’s sales director forOEMs and fleets, notes that if one is keeping equipment seven to ten years, itmakes sense to go with LEDs. But don’t consider only the cost of lamps. “Lookat the lighting and harness system as a package, not as individual components,”Gilbert emphasizes. “Make sure the lighting package is married to the harnesssystem and that they are a good fit.”
Spec’ correctly to prevent corrosion. “You may have the bestlighting in the world but if the harness is full of corrosion that causesprogressive damage to your lighting, you really haven’t gained anything,” saysGilbert. Hard-shell type connectors have a better track record versus molded,incandescent-style plugs. “You need to have a sealed system, because corrosion,water and the cocktail mix of ice-melting chemicals will wick into the wire andgo its full length, given enough time.”
Gilbert said Peterson has several fleets converting to LEDsfrom incandescents as needed, retrofitting tail lamps and keeping theincandescents as spares. “These fleets are seeing the benefit of using LEDs asstandard replacements.”
Good vs. bad maintenance
Truck-Lite’s Van Riper makes clear, “If you’re going toinvest time in maintenance, you want to do things according to good, soundelectrical practices –– and those can be found in the Technology andMaintenance Council (TMC) recommended practices (RPs).”
When they occur, many failures of LED lighting can be tracedto compromised wiring. “Spec’ from a reputable supplier and use goodmaintenance practices and you should have a wiring harness that lasts the lifeof the vehicle, barring any accidents and physical damage,” Van Riper says.
One frequent problem results from splicing wires to repairthem, which can lead to physical damage to the electrical system, says VanRiper. “Good practice and using proper heat-shrinking insulation on the repairwill make sure that you don’t have other problems in the future.” He also notesthat it is still the practice among some fleet technicians to use an “ice pick”to penetrate the wiring’s insulation to troubleshoot.
“We used to call those ice-pick circuit testers ‘murderweapons’ because if you puncture the insulation, you jeopardize the wholesystem by providing an entry point for corrosion,” says Grote’s Large.
“In today’s trucks, there’s no place for that practiceanymore,” adds Truck-Lite’s Van Riper. “Technicians need to use a multi-meterand find a place such as a connection where they don’t compromise the integrityof the electrical system.”
On maintenance, Peterson’s Gilbert says, “Followmanufacturer’s maintenance recommendations –– I can’t stress that enough.” Heexplains that if you do maintenance the way it should be done, “you shouldgenerally have trouble-free equipment for a long time” and the need for extramaintenance can be minimized.
Truck-Lite’s Van Riper points out that there is a new TMC RPon using dielectric grease to inhibit corrosion. Van Riper warns, “Just use alight coating, so you don’t get into hydraulic lock when you re-couple theconnector.” Hydraulic lock occurs where there’s too much grease, and because ofits fluid pressure, the excess grease ultimately pushes the connectors apart.
Grote’s Large explains that dielectric grease contributes tothe performance of the lamp by enhancing the connection. “What will destroy anLED is the connection; it’s usually not a circuit board failure,” says Large.“Where the connection hasn’t been made properly, corrosion will enter and killthe lamp.”
Grote considers it so important that all of their lamps comefrom the factory with dielectric grease. Because the connection is the mostimportant piece, he says, “Don’t only look at the front of the lamp, look atthe back of the lamp. Check to see if there any gaps in the pigtail.”
Training
Providing training does not hinge on a good or badeconomy, according to Grote’s Large. “If I were a director of fleetmaintenance, I’d really tighten up on repair procedures.” He strongly believesin fixing it right the first time. “If an item fails again and again, be sureit was correctly repaired in the first place. Monitor your technicians to makesure they’re doing proper repairs.” Technicians need to have the expertise andthen they must put that knowledge into practice. To help make sure techniciansare properly educated, Grote offers electrical and lighting training in its“Know-How” program. In addition to two instruction manuals, specially tailored“Tools of the Trade” training courses include hands-on demonstrations onsite withthe proper tools and supplies. Technicians participate in the demonstrations sothey learn the proper techniques first-hand. Everyone makes a sample connectionand passes it to their neighbor in class, who tries to pull it apart, Largeexplains. “The experience can be a real ego-buster if your connection breaks,but it’s all in the spirit of learning and building better technicians,” henotes. These popular courses will soon be online. “Because freight is down, nowis the time for fleets to really step up their emphasis on getting theirtechnicians properly trained because freight will come back,” says Large, “andwhen it does, have your techs ready.”
