“We anticipate a minimum service life of 100,000 hours,” says product manager Sascha Müller, adding that the service life is highly dependent on how much the prevailing temperature remains within the tolerance range during operation. The standard test is performed at 25 degrees. “In Germany, the annual average is just 10–12 degrees Celsius, which helps extend the service life.” As a rule of thumb, a decrease of 10 degrees Kelvin doubles the service life. Müller puts it simply: “Heat is often lethal for LEDs.”
Four cables are required to connect the LED boards: two for the positive and negative poles for the DC supply, as well as two more for the vitally important temperature monitoring circuit. “We’ve integrated temperature diodes into the modules, giving us the capability to measure the temperature of the LEDs in the light driver and keep it within the tolerance range,” says Müller. If it gets too hot, the light reduces the power or, if necessary, shuts off completely. Once the components have cooled down sufficiently, the lights switch back on automatically. Ultimately, operational reliability and longevity are the essence of this control concept.
Nordeon uses the 2060 Series SMD PCB Terminal Blocks, reworked by WAGO over a year ago, to connect the LED circuit boards to the drivers of these outdoor lights. Functionally, the term “driver” refers to the LED electronic ballast unit, which is responsible for the entire control of the lighting equipment, as well as the DC power supply delivering 24 volts per module. If two modules are connected in series, the voltage increases to 48 volts.