By J. Bryan Vincent
Ten years ago, the sign industry went through a major conversion cycle in which light-emitting diodes (LEDs) displaced neon as the incumbent technology for illuminating channel letters. Given the relatively high costs of neon, its power requirements, its ongoing service needs and the risk of breakage, the benefits of switching to solid-state, longer-lasting, energy-efficient LEDs were compelling.
As existing signs were converted, the process varied, from (a) removing just the neon lighting itself and applying LED modules within the letters on-site to (b) pulling the letters down completely and replacing or refacing them in a sign shop to (c) replacing the sign outright with a new set of letters.
The choice of approach depended on the location, the size of the sign and other factors. So, a variety of approaches were taken. With larger signs where the letters could not be pulled down cost-effectively, routed sub-panels were often prepopulated with LEDs and then inserted into each letter on-site, to help minimize installation time and costs.
Today, the sign industry is in the early stages of a second wave of the conversion cycle, where T12 high-output (HO) fluorescent lamps in sign cabinets are being replaced with LEDs. In fact, there are already a vast number of systems available in the marketplace for retrofitting single- and double-faced sign cabinets of any depth.
A different equation
Compared to channel letters, retrofitting a cabinet sign is a bit of a different equation. For one thing, the underlying fluorescent illumination source is already much less expensive, lasts longer and is much more efficient than neon. Other than smaller wall signs, cabinets are larger than letters, which may make them impractical or even impossible to take down, suggesting the need for on-site work.
Fortunately, sign cabinets use fixed-length T12 HO lamps. The spacing of these lamps lends itself to the easy installation of low-cost LED products that also take advantage of fixed units of measurement.
Early ‘carpet’ or ‘ladder’ LED systems for sign cabinets were primarily developed for newly constructed signs. While they were relatively fast and easy to install at a sign shop, they proved cumbersome in the field, especially for installers working from a bucket truck. As a result, many signmakers opted instead to simply adhere LED modules to an extrusion and then fix it inside the cabinet.