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What Happened to the 100000 Hour LED Bulbs?

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Re: What Happened to the 100000 Hour LED Bulbs?

#271

Post by manmal »

telchar wrote: post #248
mrb wrote: post #235

Lifetime isn't even my #1 concern with LED bulbs. It's strobing/flickering. I film all the LED bulbs I buy in slow motion at 240 fps with an Android phone, and play the movie back on a PC with mplayer using the dot(".") key to move frame by frame. Here is a shot I made comparing 2 brands of LED bulbs: https://youtu.be/QbenId_F2RQ (Edit: yeah you don't have to transfer to a PC, just playing back in slow motion on the…

Perhaps dimmable LED bulbs would be better in that regard? The LED dimmers on the market use a very high rate PWM (afaik) to prevent/minimize flickering at low brightness. I would guess that the dimmable bulbs are designed to work well with intermittent power and so wouldn't have the same problem. Of course it's still hit or miss, compatibility between bulbs and dimmers seems to be very hard to judge without testing…

Dimmable LEDs are not automatically flicker-free. My father had very cheap dimmable ones, and I complained at every visit about the strobe effect until he bought flicker-free ones.

Most dimmers work via pulse width modulation [1], i.e. the power supply is switched on/off in a different interval (more off time means lower brightness). A true flicker-free dimmed LED has to be dimmed in an analog way (probably only feasible for "dumb" light bulbs). PWM of 20kHz or something might also work, but who knows what that does to brain waves.

1: https://www.waveformlighting.com/film-photography/an-introdu...

Re: What Happened to the 100000 Hour LED Bulbs?

#272

Post by rmu09 »

brianpgordon wrote: post #113

Why are they putting electrolytic capacitors in these light bulbs? The SM2082D datasheet specifically calls for an electrolytic cap, but wouldn't a power ceramic cap last longer? 4.7uF is doable with ceramics. Is it just a really minor cost thing, and hoping the bulb fails so you have to buy a new one?

Could be the driver is designed for a specific range of equivalent series resistance of the capacitor. High ESR could help with peak current and EMC.

Re: What Happened to the 100000 Hour LED Bulbs?

#273

Post by ph0rque »

Somewhat related, I am collaborating with someone on building an indoor aquaponics system, and he's ready to pick out LED lights. We both are really confused by all the acronyms (PAR, PPF, PPFD, etc). Does anyone have a good, ELI5 (or ELINP: Explain Like I'm a Normal Person) article on what to look for?

Re: What Happened to the 100000 Hour LED Bulbs?

#274

Post by sosuke »

mrb wrote: post #235

Lifetime isn't even my #1 concern with LED bulbs. It's strobing/flickering. I film all the LED bulbs I buy in slow motion at 240 fps with an Android phone, and play the movie back on a PC with mplayer using the dot(".") key to move frame by frame. Here is a shot I made comparing 2 brands of LED bulbs: https://youtu.be/QbenId_F2RQ (Edit: yeah you don't have to transfer to a PC, just playing back in slow motion on the…

I'm really happy to see you post this. Everyone else I've brought it up too just says I'm crazy. I might be crazy but not about the damn flickering/strobe.

Especially when my dog bounces around it looks like she is in a strobe light. I did a couple of videos of it just to "prove" it in some fashion.

https://www.youtube.com/watch?v=DddB_0QrV_8

Re: What Happened to the 100000 Hour LED Bulbs?

#275

Post by simongr3dal »

RankingMember wrote: post #134
neonkiwi wrote: post #112

Earlier quoted context omitted.

I was surprised at the early failures of my Sylvania bulbs. Had expected that going with a brand that has been in the light bulb industry for a long time, I would get decent quality, but they've all died in under a year. Now IKEA bulbs are my go-to, the mix of selection, quality and price is impressive compared to what I've seen but I haven't thoroughly researched this. Do Philips or GE do better?

The last I looked at them, Ikea bulbs ran hot the packaging advised not to be used in small/enclosed fixtures because they could overheat. Do you find that to be the case with the ones you're using?

I have a couple of 2W/80lm ikea bulbs for bedside lighting, and they are room temperature.

I also own some 5W/400lm ikea bulbs for general room lighting and they do run warm, maybe something like 40°C ± 5°C. The fixture/thingy around the bulb is roughly the size of a fist.

The bulbs are pretty new so I can't say anything about the lifespan of the bulbs, but the price is reasonable, they are not the fancy smart bulbs.

Re: What Happened to the 100000 Hour LED Bulbs?

#276

Post by sosuke »

telchar wrote: post #248
mrb wrote: post #235

Lifetime isn't even my #1 concern with LED bulbs. It's strobing/flickering. I film all the LED bulbs I buy in slow motion at 240 fps with an Android phone, and play the movie back on a PC with mplayer using the dot(".") key to move frame by frame. Here is a shot I made comparing 2 brands of LED bulbs: https://youtu.be/QbenId_F2RQ (Edit: yeah you don't have to transfer to a PC, just playing back in slow motion on the…

Perhaps dimmable LED bulbs would be better in that regard? The LED dimmers on the market use a very high rate PWM (afaik) to prevent/minimize flickering at low brightness. I would guess that the dimmable bulbs are designed to work well with intermittent power and so wouldn't have the same problem. Of course it's still hit or miss, compatibility between bulbs and dimmers seems to be very hard to judge without testing…

My oven has a high / low switch for the LED lights and I can't have it on low because the strobe/flicker drives me nuts.

Re: What Happened to the 100000 Hour LED Bulbs?

#277

Post by [deleted] »

rayshan wrote: post #131
wil421 wrote: post #6

My father in law is a general contractor and religiously keeps all his LED bulb receipts. If anything goes out before the listed hours he returns it to HomeDepot. He hasn’t had any issue so far including some of the older bulbs described in the article.

Pro tip: Home Depot recently started to allow receipts to be pulled up and items to be returned with just a credit card. Ikea does this too if you always scan your Family Card.

[deleted]

Re: What Happened to the 100000 Hour LED Bulbs?

#278

Post by brianpgordon »

rmu09 wrote: post #272
brianpgordon wrote: post #113

Why are they putting electrolytic capacitors in these light bulbs? The SM2082D datasheet specifically calls for an electrolytic cap, but wouldn't a power ceramic cap last longer? 4.7uF is doable with ceramics. Is it just a really minor cost thing, and hoping the bulb fails so you have to buy a new one?

Could be the driver is designed for a specific range of equivalent series resistance of the capacitor. High ESR could help with peak current and EMC.

You have to add a resistor across the cap anyway according to the wiring diagram. I think dfox is probably right that it's a voltage rating thing.

Re: What Happened to the 100000 Hour LED Bulbs?

#280

Post by 0xffff2 »

lucb1e wrote: post #218

... so what happened to the 100k hour LED bulbs? It never answers the question. It has an anecdote about the author's own lamps that ran an estimated 15-20k hours with an advertised lifespan of 30k and have degraded to the point where they will replace them. That's n=1 and nowhere near 100k hours, or even 50k as the author mentions early-adopters will remember seeing advertised. The article contains a lot of info, bu…

Closest I saw to an answer was the last sentence of the "Color Shift Happens But is Unpredictable" section.

>It’s possible that the reduced lifetime ratings we see on current bulbs simply reflect better knowledge about actual performance of existing LED technology over time.

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