LED tray before and after wear

[Oliver]

There’s quite a noticeable difference between these Tamlite LED emergency light gear trays. It seems the phosphors were becoming burnt on the worn one. Also I’m not sure why the rating on the stickers say 230v, as these are 50v AC/DC slave lights and running them on 230v will make them blow up lol

[Ash]

I'd guess the resin containing the phosphor is delaminating from the rest of the chip package from the heat, and moisture getting in and corroding the metal parts

They prolly dont have many hours on them but if they overheated once during an outage then the chips will start corroding since this time even if they are not powered

[Oliver]

These fittings didn't really have any signs of water ingress. They were running on a slave emergency light system 24/7 and during power cuts, they would have been under driven if anything due to the central battery failing. The LEDs had suffered phosphor degradation. The fading of the PCB is likely from UV light and possibly heat from LEDs.