By FRC Staff
LED lighting is the hot new item in almost everything now—from home lighting to indicator lights, aircraft lighting, and now even emergency scene lighting. What is LED lighting and what are its true benefits vs. some of the hype surrounding it? How can aircraft rescue and firefighting (ARFF) vehicles benefit from this new technology?
LED stands for light emitting diode. A diode is a solid plate that allows electrons to only flow in one direction across it. Since it is a solid plate, it is very durable. Diodes in different forms have been around for more than 100 years. Thomas Edison worked with them and had a patent for a type of diode.
Diodes that emitted light were developed in the 1960s and were first seen as little red lights on displays for calculators and clocks in the 1970s. LEDs that produce a significant amount of white light are relatively new and are rapidly finding new applications.
One of the biggest benefits of LEDs for ARFF crews, and which is often overlooked, is the color spectrum of light they put out. LED light output is whiter and closer to daylight compared with other light sources. This whiter and more natural light, will allow you to see the true color of things. This could be important, for example, when you are called out for a fuel spill on a rainy night. The aircraft environment has a lot of different fluids such as, deicing, anti-icing, hydraulic, engine oil, jet fuel, 100 low lead, and so on. Many of these fluids are color coded. The brightness and closer to daylight effect of LED lighting will help you to see and identify these fluids.
Efficiency is another benefit of LEDs. With an LED 12-V light, like the FRC Spectra, you will be able to light up as much of the emergency scene as with a 750-watt, 110-V halogen light. The FRC Spectra uses 13 A on 12 V. Just about all smaller-sized trucks should not have a problem powering two of these lights. You can get a lot of light from a small truck that does not have an AC electrical system.
For large lighting requirements, the FRC Spectra Max light offers a 28,000-lumen output and also has a special lens that provides a ground-illuminating flood with a built-in spotlight. This will light up more of the scene than a 1,000-watt halogen on a 240-V system. The Spectra series of lampheads is available in 12- to 24-VDC and 120- or 240-VAC models. So, now you can have all of this light from 12 V. However, you need to be careful when you start adding a lot of powerful LED scene lights on a 12-V system. The high light output of the Spectra Max will require 19 A from a 12-V system. All LED light manufacturers have a similar amp-to-light ratio requirement. So although LEDs are efficient, you still need to keep track of your total amp draw. If you add enough of them you will overload your 12-V system.
An excellent option for the larger light requirements of the larger trucks is to go with 240- or 120-V LED light. A 240-V Spectra Max will still produce 28,000 lumens of white light while only drawing 1.4 amps off the AC system. With just 1.4 amps, this will give you a lot of other options for your AC electrical system.
The efficiency of LED lighting permits you to put more lights on an existing truck. If you go to a smaller LED, like the Spectra 900, it will only require 6 A from a 12-VDC system. This light puts out a good ground flood that is perfect for the sides and rear of a truck. It is easy to install and requires no panel cut outs.
Reliability is also a strong point for LED lights. Since they do not have a filament that will burn out or a glass bulb to break, they are suitable for a rough environment.
A common misconception about LEDs is that they do not produce heat. They do produce heat and, if they get hot enough, they will burn out. The small red and green indicator LEDs are operating at such low power that they do not put out any noticeable heat. But once you go to a larger white LED, it will put out heat that will need to be cooled. Most of the time these lights are cooled with the design of cooling fins built into the light housing. As the user, you should not be concerned about the cooling.
Expect these lights to get warm and do not cover them with anything while they are operating. As a point reference; a quartz Halogen uses about eight percent of the energy for producing light. About 92 percent of a quartz Halogen’s energy consumption is used for producing heat.
LEDs are improving rapidly, but as of now, more than 30 percent of the energy goes to producing light with the remainder going to heat. However, as long as LEDs are kept properly cooled they could last up to 50,000 hours. This translates to 17 years of use if they are used eight hours a night every single night for those 17 years. Because of this reliability, the industry standard seems to be a five-year warranty on all LED scene lights. Check before you buy though.
LED maintenance consists of proper cleaning. To clean the lights, use a soft cloth with mild soap and water. Lexan light lenses are used on some LEDs and most warning lights and they should not be cleaned with abrasive materials, solvents, or most chemical cleaners such as alkaline-based window cleaners. Over time, these cleaners will cause lens degradation, causing a white film, and the lens will become brittle. If you are installing lights with Lexan covers, be careful not to let Locktite or similar products touch the Lexan. If Lexan is exposed to Locktite type products, it will cause cracks in the Lexan—often within 24 hours.
LEDs should give you long-lasting virtually maintenance-free lighting for the life of your apparatus.