Making sense of LED product quality

John Bullock

John Bullock of John Bullock Lighting Design reviews
specification guidance published in 2011 by the
Lighting Industry Liaison Group.

Knowing whether an LED luminaire is any good at doing what it says on the tin has long been a bugbear of the lighting specifier, so we are all grateful to the Lighting Industry Liaison Group for coming up with 'Guidelines for Specification of LED Lighting Products 2011' - and even more grateful to those companies who've taken up the challenge of reporting the performance of their luminaires in this format.


So what's it all about?

The Liaison Group has asked all of those questions that we like to quiz company reps about when they come to call. It goes like this:

What is the Initial Lumen output of the LED luminaire?

What is its Lumen Depreciation over a stated life period?

What is the expected Failure rate over the stated life period?

What is the initial Colour Temperature and what shift is likely by the time it reaches 25% of its rated life.

What is the Colour rendering Index and what is the expected shift in CRI by the time it reaches 25% of its rated life?


And in terms of electrical performance …

What is the total power consumed?

What is the initial Power Factor and what is the expected Power Factor by the time it reaches 25% of its rated life?

This is all great stuff and should cut down on the amount of time you spend making cups of tea for LED reps when they come a-calling.

And if you're looking at catalogue information that doesn't include this kind of detail - chuck it away, because you wouldn't want to be specifying stuff that you don't know about - now would you!