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Electronics => Power & Renewable Energy => Topic started by: cdev on November 25, 2018, 07:20:58 pm

Title: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on November 25, 2018, 07:20:58 pm
I'm soo sick of buying LED bulbs that burn out in just a few months or years time, that I would really like to know of some that last many years, reliably. Do any such bulbs exist?

Sometimes I just want to put a bulb where its going and forget it, and know its not going to burn out for a long time. Seems like the claims of bulb durability mean less and less, and now are more than a bit hyperbole.

Suppose I was willing to pay more, and sacrifice some brightness, to get a truly durable LED bulb with its driver? 

When a bulb absolutely must not burn out, because say its somewhere its a real PITA to replace, which ones would you buy?
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: SeanB on November 25, 2018, 08:00:16 pm
The ones they shove on top of transmitter masts come to mind, though they generally only come in red.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: Red Squirrel on November 26, 2018, 02:34:26 am
The ones they shove on top of transmitter masts come to mind, though they generally only come in red.

TBH even those go out every year or so.  I work at a NOC and see tower light alarms regularly enough.  Though a lot of them are still incandescent I think.  I assume the reason is that you actually want them to get hot, so that they can prevent snow accumulation.

Most of the issue with LED lights is the cheap crappy drivers that are built down to a cost.  It's a shame too since the actual LED modules themselves rarely fail, but most of the time the bulbs arn't repairable (can't open without breaking) so you end up throwing out the whole bulb.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: Cyberdragon on November 26, 2018, 09:08:34 am
It's a shame too since the actual LED modules themselves rarely fail, but most of the time the bulbs arn't repairable (can't open without breaking) so you end up throwing out the whole bulb.

Yeah they do, they are shitty and Chinese too (at least the higher power ones), just watch Bigclive's channel. You can fix them by bypassing the blown chip/chipset but it might not last long after.

This is why I rant against this whole "go LED, it's so much greener!" crap. No, it's not entirely, it's polluting manufacturing to generate e-waste crap! If my bulbs are gonna blow anyway, I'd rather not have bangs and acrid smoke. :rant: Granted, haven't had any of the 50 cent LED bulbs blow up which is amazing, but I'm not sure if that's just luck.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: dzseki on November 26, 2018, 09:16:17 am
My very first LED buld was a „filament type” aka Chip-On-Glass type, it freaked out in about 1000 hours of usage. Sometimes it comes on, but it is practicall unusable, there I can see one of the LED chip is dying, and since all of them are in series one kills all... :--
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: nctnico on November 26, 2018, 09:31:08 am
When a bulb absolutely must not burn out, because say its somewhere its a real PITA to replace, which ones would you buy?
An A-brand like Philips. IIRC you can buy long-life LED lamps from Philips. These may be less efficient or use more expensive LEDs.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: SiliconWizard on November 26, 2018, 06:03:00 pm
I would either go for Philips or Osram.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: jmelson on November 26, 2018, 09:13:53 pm
I'm soo sick of buying LED bulbs that burn out in just a few months or years time, that I would really like to know of some that last many years, reliably. Do any such bulbs exist?
Well, I have been slowly converting over to LED, as the CFLs expire.  I write the install date on my CFLs and LEDs when I put them in, so I can keep track of the lifetime.  I got 3 - 5 years on the CFLs.  I have yet to have a SINGLE LED lamp go out.  I buy the "store brand" at our local hardware store, I don't know who actually makes them.    These are all exposed bulbs, not trapped in some thermally-insulating enclosure, and I have some that must be well into their second year of use.

Jon
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: f4eru on November 28, 2018, 07:35:13 pm
Quote
I'm soo sick of buying LED bulbs that burn out in just a few months or years time,
The problem lies in the "bulb" part !

Don't use led bulbs.
A sphere is optimal to keep the heat inside. It's exactly the totally wrong shape for a led lamp.

The right thing to do is not to use bulbs, which overheat, but to use lamps with the LEDs integrated, that are designed to run cool with a lot of surface for the leds and drivers to have a chance to keep cool.

Avoid led replacement "bulbs" like the plague, use led lamps.
You can often retrofit existing closed lamps with led strips, and put a 12V PSU in the ceiling.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on November 28, 2018, 07:46:10 pm
Yes, but that power supply needs to be accessible for servicing/replacement too. Maybe somebody should integrate a good quality, compact power supply into an affordable, bulb-sized case, with more than adequate heatsinking, with terminals on its bottom for the actual LED device(s). I would buy one.

Quote
I'm soo sick of buying LED bulbs that burn out in just a few months or years time,
The problem lies in the "bulb" part !

Don't use led bulbs.
A sphere is optimal to keep the heat inside. It's exactly the totally wrong shape for a led lamp.

The right thing to do is not to use bulbs, which overheat, but to use lamps with the LEDs integrated, that are designed to run cool with a lot of surface for the leds and drivers to have a chance to keep cool.

Avoid led replacement "bulbs" like the plague, use led lamps.
You can often retrofit existing closed lamps with led strips, and put a 12V PSU in the ceiling.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: floobydust on November 28, 2018, 08:48:47 pm
The problem is LED bulb manufacturers are full of patent litigation. Over heatsinking, power supply, adhesives, phosphors, LED's etc.
It's so bad the past 10 years nobody can make a reliable, low cost LED bulb without going through hoops to not infringe on someone else's patents. So the bulbs are not the best designs, many compromises.

And now I see LED manufacturers suing the retailers now, Lowe's getting sued by Epistar, Nichia suing Bed Bath and Beyond or Feit Electric, LG, Lowe's, Meridian, Everlight etc.

Ikea store lighting section and see a handful of LED fixtures flickering and cutting in and out.

Cree LED bulbs, I had about 25% of them fail within a year. You have to ship them back to Cree at your expense to claim warranty. So I ditched Cree and Home Depot also dumped them.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on November 29, 2018, 02:32:07 am
Almost all the defective bulbs I have I think are Feit bulbs.

The problem is LED bulb manufacturers are full of patent litigation. Over heatsinking, power supply, adhesives, phosphors, LED's etc.
It's so bad the past 10 years nobody can make a reliable, low cost LED bulb without going through hoops to not infringe on someone else's patents. So the bulbs are not the best designs, many compromises.

And now I see LED manufacturers suing the retailers now, Lowe's getting sued by Epistar, Nichia suing Bed Bath and Beyond or Feit Electric, LG, Lowe's, Meridian, Everlight etc.

Ikea store lighting section and see a handful of LED fixtures flickering and cutting in and out.

Cree LED bulbs, I had about 25% of them fail within a year. You have to ship them back to Cree at your expense to claim warranty. So I ditched Cree and Home Depot also dumped them.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 04, 2018, 04:29:17 pm
Costco.  I purchased 30-45 LEDs from Costco about 4 years ago and replaced every bulb in my house.  That was 4 maybe 5 years ago.  I have yest to have one fail.  And the color looks good too.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 05, 2018, 07:06:29 am
I have a bunch of the Philips remote phosphor LED bulbs, they'd the odd looking tri-lobe things, one of the first good LED bulbs on the market. I bought them in 2011-2012 and while they're not as efficient as the latest generation, I can't even comment on the lifespan because not a single one of them has failed yet.

My mom's house has a lot of recessed can lights, something around 25 of them. Over a period of several years starting around 2012 I retrofitted them with Cree recessed retrofit modules, these are a bit more efficient and have a 90+ CRI, again not a single failure.

Philips and Cree both have made some very good bulbs, the key is to buy good quality ones, not the cheapest. Look for stuff that is rated for 25,000-50,000 hours, a lot of the low cost lamps skimp on the heatsinking and are only rated for 15,000 hours. Also be mindful of the application, many LED bulbs are not intended to be used in fully enclosed fixtures and doing so will lead to early failure, bulbs rated for fully enclosed use are available.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on December 05, 2018, 01:20:27 pm
I wonder what the best LED bulbs are for outdoor use in extreme low temps?

Florescent bulbs really don't like cold weather! (Many just refuse to work at all!)
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: OwO on December 05, 2018, 04:05:00 pm
Pretty much all light fixtures in China now use LED strips plus a power brick, mounted into a large rectangular thing on the ceiling. There is an aluminum backing which dissipates the heat. The LED strips run cool and rarely fail, and if they do fail it's trivial to replace (just unscrew the strip from the aluminum plate and disconnect it). I have never seen anyone use a LED "bulb" in a standard lightbulb holder.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 05, 2018, 08:10:09 pm
I wonder about LED efficiency.  I have purchased (and returned) some LEDs where the base gets really hot.  Almost as hot as the glass of an incandescent bulb.  While others remain cool.  Anyone found something similar?

The big gripe I had about LEDs few years ago was with the color.  But looks like that issue has been solved.
LEDs are pretty much a commodity right now.  Doesn't matter what brand you buy, they are all about the same.  And they all claim to have the same "Will Last 40 years" BS warranty.  These things are only a few dollars (US).  In 3 - 4 months will pay for itself.  Yes a few from all brands will statically fail prematurely, but that's the way it goes.  I've noticed at the big box stores they have clarance sales and one can buy LEDs for less than $1,00.



Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 06, 2018, 10:44:44 pm
The efficiency is easy to find out, just measure the power draw and compare the light output, you can find independent test results of many of the lamps out there where someone has measured them in an integrating sphere.

I suspect the temperature has more to do with the efficacy of the heatsink, a major challenge with LEDs has been that while they produce relatively little heat, they radiate almost none as IR and instead it all ends up in the tiny die and has to be extracted somehow to prevent very high temperatures. Heatsinks are one of the most expensive components in a retrofit bulb so they're what tends to be sacrificed to get the cost down. Some of the low cost bulbs can hold up well under ideal thermal circumstances, but use one in a fixture that traps the heat or a hot climate and the temperature of the bulb can skyrocket. 
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: OwO on December 07, 2018, 09:18:00 am
The problem lies in the "bulb" part !

Don't use led bulbs.
A sphere is optimal to keep the heat inside. It's exactly the totally wrong shape for a led lamp.

This. Even with the best heat sinking you will not get decent thermal conductivity in that form factor, at least with passive cooling. I have looked at all of the A-brand LED bulbs and none keep package temperature below 50 degrees C. If you look up the LED lifetime vs temperature graphs, you will see that 50 degrees **junction** temperature is the absolute maximum you should go to before lifetime is severely degraded (50% brightness in just a few years), and same for efficiency. The only two solutions therefore are (1) a fan or (2) a large surface area fixture, like those mounted flat on the ceiling. Since no one wants a noisy lamp (2) is the only option left.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 07, 2018, 06:02:48 pm
Well like I said, I've had LED bulbs going in my house since 2011. There is a Philips 8W bulb in the porch light which is on a timer that runs it from dusk till dawn, and it was installed October 2011. I removed it recently and put it side by side with an identical bulb that I never ended up using and the brightness was identical to my eyes. I calculate that out to around 30,000 hours it has on it and it still looks identical to a brand new one.

Previously I used CFLs and I was doing well to get 1.5 years out of one in that light. They lasted a lot longer in that application, started once per day and run for a long period than elsewhere in the house where lights get switched on and off a lot but still not nearly as long as LED.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: IanMacdonald on December 10, 2018, 05:38:51 pm
Some time back I made up a couple of retrofits for wall uplighters using COBs, heatsinks and good quality drivers. They worked well. I changed them a while back for shop-bought LED bulbs because I was looking at selling the place and I wasn't sure what a buyer would make of my obviously homebrew (but perfectly safe) arrangements. Well, I started getting some nasty headaches working in that room. Turns out the shop-bought LEDs flicker really badly, at a frequency just outside of the visible range. (100Hz) So badly that if you wave your hand in front of your face you would think you were in a disco with a strobe going.

I did a few tests with a scope and photodiode, and found that flicker is a really widespread problem with commercial bulb-style LEDs. The worst type are the ones that look like a filament bulb, but any bulb-type LED may flicker. Meanwhile, CFLs got a lot of bad press for allegedly causing headaches, but a similar test shows that most CFLs don't flicker to anything like the same extent.

This was a surprise finding, and it really brings questions on whether we should be replacing CFLs with LEDs. Thing is, before purchase we have no way of knowing if a given brand of LED does flicker, and it isn't always the cheap ones that do.

One workaround is to use DC PSUs and LED strips, which are not going to flicker if the PSU is any good. I've done that in the kitchen. For some of the others I've put the CFLs I had in storage back in.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 10, 2018, 06:43:45 pm
Some time back I made up a couple of retrofits for wall uplighters using COBs, heatsinks and good quality drivers. They worked well. I changed them a while back for shop-bought LED bulbs because I was looking at selling the place and I wasn't sure what a buyer would make of my obviously homebrew (but perfectly safe) arrangements. Well, I started getting some nasty headaches working in that room. Turns out the shop-bought LEDs flicker really badly, at a frequency just outside of the visible range. (100Hz) So badly that if you wave your hand in front of your face you would think you were in a disco with a strobe going.

I did a few tests with a scope and photodiode, and found that flicker is a really widespread problem with commercial bulb-style LEDs. The worst type are the ones that look like a filament bulb, but any bulb-type LED may flicker. Meanwhile, CFLs got a lot of bad press for allegedly causing headaches, but a similar test shows that most CFLs don't flicker to anything like the same extent.

This was a surprise finding, and it really brings questions on whether we should be replacing CFLs with LEDs. Thing is, before purchase we have no way of knowing if a given brand of LED does flicker, and it isn't always the cheap ones that do.

One workaround is to use DC PSUs and LED strips, which are not going to flicker if the PSU is any good. I've done that in the kitchen. For some of the others I've put the CFLs I had in storage back in.

I have noticed the flicker too.  Some are really bad, while others aren’t as bad.  All of the LEDs I purchased from Costco, HomeDepot and Lowes have not caused headaches for anyone in my family.

This is going to sound crazy...  There’s a TED talk about light flicker curning Alzheimer’s disease in rats.  The talki was given by a women with a Chinese accent.  I can’t find her TED talk, bout here’s a YouTube about the research she’s doing at MIT.  Her research is only in rats, but that’s not stopping from companies trying to make a profit and making unsubstanted claims of being able to cure Altzheimer’s.  It’s a 40 he flicker.  Interesting story of how she figured this this out.

https://youtu.be/O_p4QWkE2Ls


 
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 10, 2018, 06:45:20 pm
Just found the article.

http://news.mit.edu/2016/visual-stimulation-treatment-alzheimer-1207 (http://news.mit.edu/2016/visual-stimulation-treatment-alzheimer-1207)
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: jmelson on December 10, 2018, 08:17:59 pm
Well, I started getting some nasty headaches working in that room. Turns out the shop-bought LEDs flicker really badly, at a frequency just outside of the visible range. (100Hz)
A quick way to tell is if the LED lamps go black instantly when you turn them off, they likely have minimal to no capacitors in them.  If they fade slowly to black over a second or so, they must have some really decent caps in them.  The ones we have here seem to fade out, so I guess that is good.

Jon
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: schmitt trigger on December 10, 2018, 08:42:30 pm
Phoebus cartel, anyone?

https://en.wikipedia.org/wiki/Phoebus_cartel

Now seriously, I don't think there is a similar cartel for LED lamps. Rather, as one has explained, the culprits are the sh!itty drive electronics and/or poor thermal management.

Like James_s, I also write the installation date on the body. I have a few installed outside with an automated photocell turn on/off, and so far have worked reliably every night for close to 8 years. They were made by Toshiba.

Also.........My living room ceiling is tall (18 feet) with several ceiling-recessed lights that would be an incredible pain in the anode to replace.
In the long and sweltering summers down here, even with the extra insulation, the ceiling on its own becomes quite warm. 

I know that heat is an effective electronics killer, therefore for those lights I wired a dimmer which is permanently set at 80% level. (The bulbs are dimmable), in an effort to run them cooler.
I don't have enough data to claim that my theory will provide a longer life, but I strongly suspect it does.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 10, 2018, 08:55:52 pm
I always buy the smalles package of lamp I can find first and spend some time evaluating the lamp before I buy more.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on December 10, 2018, 09:18:48 pm
Wow..

Quote
https://spectrum.ieee.org/tech-history/dawn-of-electronics/the-great-lightbulb-conspiracy

"There were continual reports of cartel members’ attempts to restore the burning time of their bulbs to the old levels in defiance of the watchful eyes of Phoebus. At one point, some members surreptitiously introduced longer-lived bulbs by designing them to run at a voltage higher than the standard line voltage. After the Phoebus development department’s customary report of voltage statistics revealed such product “enhancements,” Anton Philips, head of Philips, complained to an executive at International General Electric:

“This, you will agree with me, is a very dangerous practice and is having a most detrimental influence on the total turnover of the Phoebus Parties…. After the very strenuous efforts we made to emerge from a period of long life lamps, it is of the greatest importance that we do not sink back into the same mire by paying no attention to voltages and supplying lamps that will have a very prolonged life.”

As this episode reveals, tweaking a lightbulb’s rated voltage was one way to modify the product’s life. Another was to adjust the current, as GE engineers did to decrease the life span of its flashlight bulbs. A GE flashlight bulb in the precartel days was designed to last longer than three changes of batteries. This life span was then cut to two battery changes, and in 1932 the GE engineering department proposed that the bulb last no longer than one battery. A GE engineer named Prideaux wrote in a memo, “We would suggest increasing Mazda lamp No. 10 from .27 ampere to .30; and 13.14 and 31 from .30 to .35. This would result in increases of candlepower of 11 and 16 percent respectively.” That boost in illumination, he suggested, “would be acceptable to all flashlight users” despite the fact that the higher current would shorten not just the bulb’s life but also the battery’s."


Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 10, 2018, 10:49:10 pm
Phoebus cartel, anyone?

https://en.wikipedia.org/wiki/Phoebus_cartel

Now seriously, I don't think there is a similar cartel for LED lamps. Rather, as one has explained, the culprits are the sh!itty drive electronics and/or poor thermal management.

Like James_s, I also write the installation date on the body. I have a few installed outside with an automated photocell turn on/off, and so far have worked reliably every night for close to 8 years. They were made by Toshiba.

Also.........My living room ceiling is tall (18 feet) with several ceiling-recessed lights that would be an incredible pain in the anode to replace.
In the long and sweltering summers down here, even with the extra insulation, the ceiling on its own becomes quite warm. 

I know that heat is an effective electronics killer, therefore for those lights I wired a dimmer which is permanently set at 80% level. (The bulbs are dimmable), in an effort to run them cooler.
I don't have enough data to claim that my theory will provide a longer life, but I strongly suspect it does.

You had better believe there is a cartel....  The Chinese cartel.

I doubt dimming will reduce the heat from the LEDs.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 10, 2018, 11:19:46 pm
They run far cooler when dimmed. Why would you think otherwise?
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 10, 2018, 11:53:20 pm
They run far cooler when dimmed. Why would you think otherwise?


Running at reduced voltage would increase the amperage resulting in less efficiency and same or more heat if were not dimmed.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: beanflying on December 11, 2018, 01:16:44 am
Amazing several times here flickering LEDS are the problem. Seriously on an EE forum flickering leds are not the problem the problem is the drivers and the supply! And to ecological damage of LEDs yeah because the Mercury in CFL's were awesome for the environment  :palm:

There is a similar thread running on filament bulbs here for those that haven't seen it. https://www.eevblog.com/forum/chat/fialment-style-led-bulbs/msg2027542/#msg2027542 (https://www.eevblog.com/forum/chat/fialment-style-led-bulbs/msg2027542/#msg2027542) 'Some' bulbs are starting to run decent drivers in them but keep demanding $0.02 less cost on an item and you will get bad flicker. The IC on the photo below can be sourced for between $0.06 and $0.10 each here https://lcsc.com/product-detail/LED-Drivers_SM2082ED_C80717.html (https://lcsc.com/product-detail/LED-Drivers_SM2082ED_C80717.html)

Blame the drivers on the shitty end of the spectrum that YOU and the dumb ass buyers for the companies in YOUR countries buy not the LED.

Failure is a different issue and Overdriving and poor cooling is the principal cause and this comes down to wanting more lumens than the next guy for pennies saved be that less LEDs or less aluminium.

Bottom line is we need to start demanding better of the entire supply chain and pay a few more cents or we will continue to get flickering lamps.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on December 11, 2018, 01:18:45 am
I think you may be confusing LEDs with incandescent bulbs. Less voltage = less current with LEDs.

They run far cooler when dimmed. Why would you think otherwise?


Running at reduced voltage would increase the amperage resulting in less efficiency and same or more heat if were not dimmed.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 11, 2018, 01:24:28 am
And less current results in dramatic efficiency gains. If you look at the lumens per watt of a typical power LED, the efficiency drops pretty significantly driving them at 700mA vs 300mA.

I haven't measured but the LED bulbs I have on dimmers run at a temperature I can hold my finger on for a second or so before it hurts so probably around 60C. Dimmed to approximately half brightness they feel room temperature to maybe very slightly warm to the touch.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on December 11, 2018, 03:15:00 am
I have a strip of bright blue-green "piranha" I think the name is, LEDs not heatsinked at all, but very bright. They are not running at their rated current or voltage drop at all, though and are cool to the touch. They have been running continuously for at least 15 years, (with a break to make a cross country trip) on the same DC power supply with NO discernible drop in brightness. Not even the tiniest bit. I use them as a hall light but the current draw is so low that it makes no sense to turn them on and off, they are just on all the time.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 11, 2018, 05:03:58 am
My flawed thinking......  Thank you.   I will stand corrected.

I think you may be confusing LEDs with incandescent bulbs. Less voltage = less current with LEDs.

They run far cooler when dimmed. Why would you think otherwise?


Running at reduced voltage would increase the amperage resulting in less efficiency and same or more heat if were not dimmed.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: IanMacdonald on December 11, 2018, 10:01:19 am
Blame the drivers on the shitty end of the spectrum that YOU and the dumb ass buyers for the companies in YOUR countries buy not the LED.

So the answer to any problem is to throw money at it.   :clap:

I think I need some $100-a-foot speaker cable. The cheaper stuff obviously must be shitty.  :-DD

Seriously, the problem here is that there is little incentive for manufacturers to fix flicker because it's not something that can be determined at point of sale, therefore they will see it as being unimportant  in terms of affecting sales volumes. I'm generally opposed to bureaucracy and red tape, but this is precisely the sort of situation where product testing and certification is valuable.  :-DMM
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: beanflying on December 11, 2018, 10:28:20 am

So the answer to any problem is to throw money at it.   :clap:

I think I need some $100-a-foot speaker cable. The cheaper stuff obviously must be shitty.  :-DD

Seriously, the problem here is that there is little incentive for manufacturers to fix flicker because it's not something that can be determined at point of sale, therefore they will see it as being unimportant  in terms of affecting sales volumes. I'm generally opposed to bureaucracy and red tape, but this is precisely the sort of situation where product testing and certification is valuable.  :-DMM

And you are being a wally for what reason exactly?

There is and will be a minor cost to fix flicker so your point is that it should happen for free to the consumer because you think it should be so?

We are talking throwing a matter of cents per lamp here and the will to change and spend it is virtually zero because of the supply chain keeps pushing the low bidder model to maximise $. Pressure has to come from somewhere a point we seem to agree on. And we agree on it being a good idea.

Certification, Regulation and then consumer education on a world scale lets get the EU to do it they love this stuff then adopt it worldwide as this certainly WON'T be FREE to implement.

Unless in your mind you have another way to make that free too?
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: cdev on December 11, 2018, 02:13:46 pm
If people were just a little more literate electronically, they would realize that better heat sink + slow fade out when power is removed = almost certain to be a better LED light.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on December 11, 2018, 03:34:09 pm
But that would requires knowledge and education.  That’s something businesses don’t like to spend money on.

If people were just a little more literate electronically, they would realize that better heat sink + slow fade out when power is removed = almost certain to be a better LED light.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 11, 2018, 05:19:19 pm
Very few of my LED lamps do a slow fade when you shut them off, and they have been long lived and don't flicker. I suspect it has to do with the way the driver handles dimming.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: schmitt trigger on December 11, 2018, 05:41:13 pm
What I meant above of a dimmer running at 80%, it was at 80% power, not at 80% voltage. Measured with a Voltech power meter.

While I was doing that, I was simultaneously measuring the lux level at a center table. With 80% input power, I was only reducing the luxes to 87% of the full power level. A nice power consumption reduction with a barely  discernible reduction in illumination. This corroborates James's statement that the efficiency decreases at the highest power levels. Come to think of it, this fact on itself would reduce heat generation.

And yes I understand the difference between lumens and luxes.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: james_s on December 11, 2018, 05:51:22 pm
Looking at a few datasheets, it seems the light output is a lot more linear with increasing current as it was in previous generations I had worked with. The output does still drop with temperature though, at 100C it is around 18% lower than it is at room temperature on the Luxeon medium power LED I just looked at.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: electromotive on March 05, 2019, 04:30:06 pm
I've had good luck with Phillips / Osram. Even the once mighty GE bulbs have failed me. I'm wondering if the GE bulbs themselves are just a licensing agreement, because they don't seem to last much longer than the no-name subsidized bulbs here in the states.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: DougSpindler on March 05, 2019, 04:41:20 pm
GE for most consumer goods is a licensing arrangement.  Other than medical equipment and nuclear reactors I don’t think GE has made any consumer products in decades.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: kaz911 on March 10, 2019, 07:57:03 am
For retrofit halogen I always put in Philips Master series. They are designed to have a “larger” turn on power consumption and “anti-flicker” so it usually works with old transformers. They might use slightly more power than other LED’s but have high CRI and rarely fail.

I have a lot of halogen that has been replaced - and I think out of about 90 bulbs where 50 are Philips Master - only 1 has failed in 3 years. But it was promptly replaced FOC by Philips.

For screw in fixtures I use Ikea’s latest - they have become pretty good for the price. :) The old ones had horrible CRI’s but the latest seems to be a lot better.
Title: Re: Longest lived standard fixture (retrofit) LED light bulbs?
Post by: ahbushnell on March 10, 2019, 04:44:56 pm
The problem is LED bulb manufacturers are full of patent litigation. Over heatsinking, power supply, adhesives, phosphors, LED's etc.
It's so bad the past 10 years nobody can make a reliable, low cost LED bulb without going through hoops to not infringe on someone else's patents. So the bulbs are not the best designs, many compromises.

And now I see LED manufacturers suing the retailers now, Lowe's getting sued by Epistar, Nichia suing Bed Bath and Beyond or Feit Electric, LG, Lowe's, Meridian, Everlight etc.

Ikea store lighting section and see a handful of LED fixtures flickering and cutting in and out.

Cree LED bulbs, I had about 25% of them fail within a year. You have to ship them back to Cree at your expense to claim warranty. So I ditched Cree and Home Depot also dumped them.

I buy LED fixtures for the garage.  The LED's are spread out over a large area and the thermal load is low.  So far so good.  Good idea to record the date.  I never think about that.