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Lamps => Modern => Topic started by: davidnonledfan on March 01, 2022, 01:27:19 PM

Title: What are the best LEDs that can work past their rated hours?
Post by: davidnonledfan on March 01, 2022, 01:27:19 PM
I came to a question now that there should be LED bulbs that are going to last a solid 7 or even 10 years, I have heard of GE LED bulbs lasting a ridiculously long time of 7 years however, I heard that Philips Home Depot LEDs are really solid as well. Sylvania LEDs are okay. I have heard of brands like MaxLite and Greenlite and they make LEDs as well. Anyone? What is the most solid and reliable LEDs made to date?
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: Medved on March 01, 2022, 01:33:42 PM
Well, the earlier LEDs were reliability wise rather a disaster and the newer ones, where the reiability problems are supposed to be solved are not here long enough to really prove anything beyond what are their manufacturers claiming.
So sticking with manufacturer and distributor who are offering long enough and are known to really honor warranty is the best course of actions. First the products they sell would be already scrutinized so any really problematic ones won't be sold anymore, plus when a problem will appear, there is a chance they will help you.
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: LightsoftheWest on March 01, 2022, 02:02:13 PM
Go with the Philips AmbientLED. I heard that an independent lab tested about 30 or so of them to about 40,000 hours. Not one failed. Here's a link to buy some. (https://www.ebay.com/itm/Philips-EnduraLED-A19-Lamp-12-5W-Model-12E26A60-/313845152250?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l6249&mkrid=711-127632-2357-0)
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: davidnonledfan on March 01, 2022, 02:15:39 PM
Hey, thanks! Good suggestion. WOW, 40k hours, that is A LOT!!!!!! almost like a Mercury vapor lamp

Do you happen to know if these bulbs can come in a color temperatures higher than 2700k?
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: LightsoftheWest on March 01, 2022, 02:27:04 PM
I think the later version (all white) was, but I haven't seen any for sale.
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: AngryHorse on March 01, 2022, 03:48:44 PM
I’ve still got an Energetic mini globe, rated at 30,000 hours that’s now on 45,158 hours run time, and it’s still as bright as the day it went in!  8)
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: bulb_tester2009 on March 03, 2022, 06:42:07 AM
I think Philips Master low-voltage LED reflector is OK, because it has an ultra-long life of 40,000 hours and a high color index of CRI90.
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: Medved on March 09, 2022, 12:30:38 AM
And one of the biggest contributor is how the heat can escape, so how hot the lamp runs. 10degC difference means doubling/halving the lifetime. So very slight difference in fixture design or its mounting may easily overcome the differences in LED assembly designs. Or evensome fixture designs may suit some LED designs and different design may make other LED design better there, so a LED type lasting the longest in one fixture may get mediocre in another.
All these aspects together make it very difficult to asses which LED will last the longest where.

What will at least help is to select a LED style that has the least losses in a particular fixture. That way you may cut down on its rated power for the same final light output and that would make quite a difference in the temperature.

So it is likely there is no "one best type suits all" and no one could tell what exactly to look for.
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: AngryHorse on March 09, 2022, 07:48:16 AM
Oh but there is  ;), what you say above is correct, but it only applies to SMT lamps, lantern and fixture parameters don’t, (or shouldn’t), have any effect on filament types?
Title: Re: What are the best LEDs that can work past their rated hours?
Post by: Medved on March 09, 2022, 02:15:58 PM
It does. The filament types just use different technology to get the heat from the LED chips to the surface and the surrounding air, but still it just results in some constant temperature difference between the chips and the bulb surface. The heat to dissipate is the same.
So when the surrounding air can not move, the bulb surface gets hotter than designed for, so do the chips inside of the bulb.
Don't get me wrong, the filament designs have their strength in utilizing the whole glass globe surface to transfer the heat to the air which is way better than just the neck area of the "SMD" models, but on the other hand they have to rely on a gas to get the heat from the tiny filaments to the bulb surface, a piece of aluminum of an "SMD" is just better at this part. Here applies the "use the lamp that best optically fits the fixture": If you have a downlighter, using a directional SMD product means all of its light goes out. But from a filament type, half of its output has to be reflected from the fixture back, so most of it would get lost. Therefore the SMD suffices with about half of the lumen output to do the same job. Now the filament LEDs use to be a bit more efficient, still the SMD power could be 2/3 of the filament one. And this 2/3 of power could easily more than offset its smaller cooling surface so yield longer lifetime. And very likely a lower cost as well (for the same quality level product).

The weakest point on LEDs, mainly when operated at elevated temperstures, are the wire bonds. Ultrasonic friction weld of a less than a mil thick wire to about um thick distribution metalization on the LED die. Mainly on the cathode side the metalization underneath the ball tends to dissolve into the ball and so crack and lose connection with the rest of the semiconductor. This then leads to the well familiar (thermal) LED flickering failure.