Behind the quality: LED lifetime
Tuesday July 9th, 2019
You may have noticed that LED lighting industry is full of confusing terms and one of them is LED lifetime.
If you look at the cheaper brands, they usually say that the lifetime of their modules is 50 000 h, understanding that it is no longer good for using. Whilst others, mostly the more quality ones, say that their products are rated 50 000 h L70. Should you pay attention to “L70” and what does it mean?
L70 is a standardized LED lifetime marking standing for the time it takes until LED light output (lumen maintenance) reduces to 70% of the initial output. In other words, the module does not shut down instantly - it slowly dims down. Thus, this standardization allows you know how long you can depend on an LED to provide an acceptable level of intensity until it has to be replaced. There are additional ratings such as L80 (80% of initial lumens) and L90 (90% of initial lumens).
When the lifetime specification does not contain L70 (L80 or L90), the product is unlikely to emit 70% or even less of its initial lumen output at the end of its life. Therefore, you can’t plan when the replacement will be needed.
Thus, if you want the product to be fully functioning the whole warranty time, and not lose more than it is declared, check if it is rated for at least L70.