Issue link: http://read.uberflip.com/i/370309
78 • September 2014 • S I G N & D I G I T A L G R A P H I C S ELECTRIC SIGNAGE "One of my pet peeves when com- paring fluorescent to LEDs is that the evaluation is usually done in an environ- ment that's perfect for the best fluores- cent performance (75F-85F degrees). LEDs, properly thermally managed, only change in intensity by about 5 percent over a 140-degree temperature range (-40F to 110F). The top LED companies do a good job of managing the thermals on their products so they have a nice long life: 50,000 hours R70, which means you have 70 percent of the light after 50,000 hours," says Southard. "Fluorescent output changes about 80 percent over that same temperature range. When it gets hotter or colder it starts to fall off in intensity, all the way down to about 20 percent. Everyone wants to base evaluation on one perfect temperature, but when you do that with LEDs you're installing more LEDs in the sign to get it to match that perfect condition, instead of putting the appropriate amount of LEDs in the sign to make it look great all year long, and in all weather conditions." US LED's Stone adds that LEDs oper- ate most efficiently at cold temperatures, which is why installations in locations with more extreme winters are on the rise. "In Canada they're using a lot of our product for retrofits because once the light fails in sub-zero temps the ballast keeps firing continuously almost to the point where it will burn the post on the tube. So, every time it's firing you're using a lot more electricity, the sign is not illuminating, and someone has to go out to fix it. And when they do fix the sign it's not just changing a lamp; you usually have to change the ballast and everything else," says Stone. On the hot side of the equation, Stone says, "Any LED product from a top-tier manufacturer is about the heat sink and how you get the heat away from the diode. The extrusion in a sign cabinet LED sys- tem is part of the heat sink engineered into it, which sucks the heat away from the LED. You're not only getting structural integrity, but you're getting the ability to draw the heat out of the module." LED manufacturers are developing a broad range of products designed to work in cabi- net signs. This installation for Wells Fargo shows Wachovia technicians using LED com- ponents from AgiLight for an interior cabinet sign. (Image courtesy of AgiLight) The LineFit Light LED system from GE Lighting is a quick and easy way to transform a fluorescent cabinet sign into an efficient LED solution. (Photo courtesy of GE Lighting) The BoxRayz LED system from AgiLight provides high efficiency and cost effective LED lighting solutions for both single and double-faced cabinet signs. (Image courtesy of AgiLight)