3 ms·

>Those which fail are likely to fail due to inadequate cooling. With good cooling even large currents cannot damage the LEDs. As long as the temperature of the

>Those which fail are likely to fail due to inadequate cooling. With good cooling even large currents cannot damage the LEDs. As long as the temperature of the LED is limited there is no need to drive it less. This seems like a logical conclusion considering lower power extends their life and the diodes that fail are usually discolored (as if they overheated). However, I'm not entirely sure it is as simple as inadequate cooling. All my high power LED floodlights are installed outdoors. I had 3 failures in the middle of winter when outside temperatures are way below zero (I remember these especially well, because climbing a tall ladder in freezing -20C wind is not something you forget easily). My theory is that they initially fail short that's why they appear burned. Also better cooling definitely extends their life, but it is not the only factor. The LED floodlights I mentioned were all housed in flat cast aluminum casings with find. The pcb is made of aluminium (with a very thin white insulating layer and copper traces on top). There is thermal paste between the back of the pcb that is raw aluminium and the case. I can't imagine a more favourable cooling solution. And still these floodlights are amongst the worst LED experiences I had. I tried all sellers available that didetry to charge >6x the price. >I do not doubt your experience, but it is possible to choose better LED lamps Perhaps it is location dependent. The lights I had a good experience with were purchased in the UK, but I've since moved to Poland. I'm happy to order from other countries within the EU (I even wanted to get the same LEDs from the UK again, but they don't sell them anymore). The brands I see around here are either noname/picked up from thin air, kobi, samsung,philips or sometimes Osram. I have to admit I haven't got much experience with Philips or Osram. All the others are the same (including Samsung Pro). I would've bought more of the Philips/Osram lights, but none of my local stores carry them in cool white, ordering one or two online seems a waste of the shipping while I'm not ordering 20 without checking them out first... (if someone says "Philips is great" I'll get a 10 pack) Also I noticed people who like warm rather than cool light seem to have a better experience overall. Two of the best LEDs I have are warm, and they look like the famous Philips Dubai bupbs(I couldn't get any cool whites with the right fitting). They have been living outside for last 7 years, hooked up to a PIR next to a cat's food&water so they are activated a lot. I've replaced the PIR sensors, but the lights are still fine. Again, these were purchased years ago. If anyone knows any good brands available in Europe, please mention them.

Eisenstein 3y ago
> All my high power LED floodlights are installed outdoors. I had 3 failures in the middle of winter when outside temperatures are way below zero An SMD LED chip is only a mm or two in size. I doubt that even a -20C wind directly on it could cool it fast enough to make a huge difference just because of lack of surface area.
- HPsquared 3y ago
  For a given power level, the chip temperature will be a certain number of degrees warmer than ambient. So if the chip is at 50C in 30C ambient, it'll be something like 30C in 10C ambient.
  - lstodd 3y ago
    LEDs don't die of being at 30C. For that I saw in dead lamps/floodlights I opened I mostly wondered how this managed to even last for the time it did. The best engineering of a LED light I ever saw is still the 2013-ish era Maglite bulb. It just works, no overheating, no nothing.
stevekemp 3y ago
I write the date I install light-bulbs on the shaft, with a permanent marker. Because I've always had a feeling that bulbs die "too often". The ones I just checked in my flat which are over four years old are all Osram. I have none older than that, due to moving house too much. To be honest I just buy whichever bulbs are on sale at the local hardware store. I've never really gone out of my way to try anything fancy or specific. I did have a pair of Hue bulbs at one point, but I got annoyed with the state mismatch between the bulbs and the switches, and always figured I'd rewire to smart switches in the future and gave up on the lighting until that time. The only thing that did stick was using a bunch of lamps in my bedroom with a 3-in-1 radio-controller for socket-switches. That's nice, to be able to toggle a bunch of lamps via a little remote in the bed.

Eisenstein 3y ago

> All my high power LED floodlights are installed outdoors. I had 3 failures in the middle of winter when outside temperatures are way below zero An SMD LED chip is only a mm or two in size. I doubt that even a -20C wind directly on it could cool it fast enough to make a huge difference just because of lack of surface area.

HPsquared 3y ago
For a given power level, the chip temperature will be a certain number of degrees warmer than ambient. So if the chip is at 50C in 30C ambient, it'll be something like 30C in 10C ambient.
- lstodd 3y ago
  LEDs don't die of being at 30C. For that I saw in dead lamps/floodlights I opened I mostly wondered how this managed to even last for the time it did. The best engineering of a LED light I ever saw is still the 2013-ish era Maglite bulb. It just works, no overheating, no nothing.

stevekemp 3y ago

I write the date I install light-bulbs on the shaft, with a permanent marker. Because I've always had a feeling that bulbs die "too often". The ones I just checked in my flat which are over four years old are all Osram. I have none older than that, due to moving house too much. To be honest I just buy whichever bulbs are on sale at the local hardware store. I've never really gone out of my way to try anything fancy or specific. I did have a pair of Hue bulbs at one point, but I got annoyed with the state mismatch between the bulbs and the switches, and always figured I'd rewire to smart switches in the future and gave up on the lighting until that time. The only thing that did stick was using a bunch of lamps in my bedroom with a 3-in-1 radio-controller for socket-switches. That's nice, to be able to toggle a bunch of lamps via a little remote in the bed.