LED Lumen Maintenance 

All light sources experience a decrease in light output (lumen depreciation) over their operating life. Lumen maintenance simply compares the amount of light produced from a light source or from a luminaire when it is brand new to the amount of light output at a specific time in the future. The light flux of HPS and HQL lamps decreases by 30% in about 4 years, and they need to be changed after that. Metal halide lamps need replacing approximately every other year. The lumen maintenance of led components depends both on the LED technology, and on the implementation of the LED light fixture; especially how much the LED components are strained with power and heat.

The figures below present the lumen maintenance of the LED components used in the Valopaa led light fixtures. At the moment we use leds of 100 lm/W, 120 lm/W and ES-series. Note the differences in indoor and outdoor use, as well as the used current input 350mA or 700mA. 

Read more about the led lumen maintenance of Philips Lumileds.

 
Led (with current 350 mA) in typical outdoor use in the Nordic climate.

 
Led (with current 700 mA) in typical outdoor use in the Nordic climate.

 
Led (with current 350 mA) in typical indoor use.

 
Led (with current 700 mA) in typical indoor use.