Singapore, 14th June 2012
The LED (quality) saga continues on a nearly daily basis! Today I went out to investigate renewed issues spotted at our first 100% LED installation at the Intercontinental Hotel. In earlier blogs last year I reported about our successes as well as about our big challenges and discoveries. The famous dust issue with the Halogen LED retrofit being one of them. But everything was seemingly resolved last year and the lamps replaced honourably by Philips. Till recently, besides the occasional issue, the installation has been operating without too many complaints, at least so I am made to believe. But recently lamps have started to flicker again for unknown reasons. But flickering lights is not something that goes un-noticed, certainly in a restaurant where lighting levels are set to create ambiance and a memorable dining experience. If the spot aimed at your table or washing the wall opposite you start to flicker intermittently, it spoils not only the mood but also the overall impression of this high class venue.
The dimming of LED’s has been one of the biggest issues that manufacturers have been dealing with specifically when it comes to retro fit LED which are supposed to fit seamlessly into an existing electrical infra-structure. In our case the infra-structure was recreated but using updated technology to enable the use of LED MR16 retrofit lamps. But still the LED / driver/ transformer selection proved to be extremely critical. The latest updates obtained from Philips today does not even show our transformer selection on its tested product list anymore!
A few questions came to our minds when testing the installation today. Is the minimum dimmed lighting level sustainable for longer durations? We had already increased the lowest dim level to about 10%, some even 15%, even though in some situations we had managed to dim close to 5%. However because there are obvious inconsistencies in the lamp-transformer combinations, some start flickering at higher values. As only one or two lamps flickered in a circuit of several connected together we could only conclude that the dimmed level output from the dimming system is consistent. Are there any aging issues, notably if an LED/transformer combination is lit consistently operated at very low lighting levels?? Last but not least are there any issues if the LED light is connected to battery powered emergency supply? To be continued…