LED Lessons learned 2
Perth, 2nd July 2014
We keep learning our way through the LED minefield…
Today my team in Singapore faced a challenge in regards to resolving a specific dimming issue related to the dimming of big decorative ballroom chandeliers that are being reconditioned to a new look with (of course) the inevitable LED retrofit. The problem that we faced initially was to find the LED lamp that could reproduce the sparkle to bring out the crystals, originally done by clear glass 40W E27 GLS lamps. The replacement was found in an 8W E27 retrofit with similar lumen package in a clear globe producing the small focal lighting point that we needed for the sparkle effect. Colour temperature a nice 2200 or 2500K, so all good.
The manufacturers information stated that the lamp was seamlessly dimmable to less than 5%, again just what we wanted. But as always due diligence called for some testing with the dimming equipment that we had agreed with the client, basically an upgrade what was already available in other areas of this hotel project. Not suspecting any major issues we were taken aback when we were informed that the initial test on the mock up showed limited dimming possibilities! What the…!
So we went out to investigate to find one of those issues that probably many of you encounter in the field. The dimming modules were designed for incandescent loads. I understand that in our case the LED load was well under the minimum load required for the leading edge dimmer to operate properly. While the dimming specialist was telling us to increase the circuit load, adding an active load is not the solution as it does not solve the root problem, it also does not react the same as the LED dimming driver!
What should be done is that the dimming systems should look at modules suitable for much smaller wattage systems! We reduced the power load by 5 times, the dimming system should adapt accordingly. We don’t realise all this when go about our LED selections, but as LED becomes standard, dimming system manufacturers should move in sync to develop LED compatible modules when it comes to dimmable loads. Lesson learned again and appropriate action taken!
Light watch 5-107: There are some impressive chandelier designs for ballrooms, I googled a few for reference…there are many lighting points in these chandeliers!