12 ms·

tl;dr: LED bulbs get too hot, lowering their life expectancy. Manufacturers need to include cheap thermistor circuits, which automatically dim the light to a sa

tl;dr: LED bulbs get too hot, lowering their life expectancy. Manufacturers need to include cheap thermistor circuits, which automatically dim the light to a safe thermal equilibrium.

benjamincburns 13y ago
Consumers need to be educated, too. Anyone using an A19 in a can-style fixture is wasting energy by lighting things they don't need lit. Use something directional like a PAR or a BR, and you can reduce the amount of wattage consumed to light a given area. Further, LED manufacturers design their directional lamps with these applications in mind. See the spiral pattern [1] on the heat sink around Lighting Science PAR bulbs? That's designed to use the thermal differential to create a nice air flow up into the fixture so that it may be used in a recessed or other partially-enclosed fixture. 1: http://www.1000bulbs.com/product/100560/LED-PAR3011HE25WW.html http://www.1000bulbs.com/product/100560/LED-PAR3011HE25WW.ht...
- Lightbody 13y ago
  It's not that simple, sadly. My house has 100+ canned recessed lights, all of which had been filled with Sylvania 50W Halogen PAR30 & PAR30LN bulbs. I have been desperately trying to find a replacement LED that matches the same warmth and color. This bulb claims to be the exact replacement: http://www.amazon.com/gp/product/B00467E3LA/ http://www.amazon.com/gp/product/B00467E3LA/ But yet this one and others that have similar lumens, temperature, and equivalent watts all don't even get close to the warmth that the halogens produced. Fortunately, I found a cheap alternative: http://www.amazon.com/Philips-424374-7-watt-Household-Dimmable/dp/B00B4CPLGG/ http://www.amazon.com/Philips-424374-7-watt-Household-Dimmab... It's the A19 40W that the article cautions against, and it looks slightly less sexy in the recessed can, but the color almost exactly matches the halogens I have (except when dimmed -- nothing can match the fireplace-like glow). What's weird is that the lumens and temperature for that bulb aren't even close to what the halogens claim, but they look almost identical. Which has made me wonder if this switch to LED is way more complex than just those two measurements :P
  - colechristensen 13y ago
    http://www.switchlightingco.com http://www.switchlightingco.com produces excellent (though expensive) LED lights which are, I'd say, 95% of what I could want out of a halogen replacement.
  - benjamincburns 13y ago
    > (except when dimmed -- nothing can match the fireplace-like glow). I can't talk specifics (under NDA from a former employer), but this is a problem for which solutions exist. I don't know that manufacturers think there's much of a market there, however. > Which has made me wonder if this switch to LED is way more complex than just those two measurements :P It is. There are a bajillion things going on. One which you've already noticed is how dimming impacts color temperature. CRI is also a huge issue. Then there's the optics - LEDs are very directional, so they require pretty advanced lenses in order to achieve a desired lighting pattern [1]. Optics impact all kinds of things, including color temperature, and since the development cost is high you can expect cheap brands to skimp there. If you're comparing them by looking directly at the bulb, internal glare/reflection is hard to match as well. I'd still caution against using the A19s in a recessed fixture. It's not a safety issue (that I'm aware of), but you definitely won't get the rated life out of the bulb. Out of curiosity, did you try an LED BR30? I think you might find one from a quality manufacturer to be a bit better than the A19. 1: $20 says the lighting pattern on the Sylvania LED is smoother/more regular than the Sylvania halogen, but I'm biased since I know the guy who designed the lens.
  - ScottBurson 13y ago
    I just put four of these in my kitchen and I think they do a remarkably good job of simulating incandescent color: http://www.amazon.com/Ecosmart-Powered-Recessed-Light-Dimmable/dp/B004OP84RS/ http://www.amazon.com/Ecosmart-Powered-Recessed-Light-Dimmab...
- Pxtl 13y ago
  It's a light bulb. A light bulb. This isn't a car, which you expect to require some expertise. It's not a furnace that will be primarily handled by an HVAC specialist. It's a light bulb. Consumers have a reasonable expectation that devices like this Just Work. If the device fails to meet its promised service-level without a dozen asterisks in its usage? It's not meeting its intended purpose and it's defective. Consumers should not have to meticulously research every small purchase. Simple, small purchases of replacement parts should not require reading a 10-page instruction manual of 6-point font, especially since you didn't get this manual until after you got the damned thing home. By allowing manufacturers to sell these defective devices, we don't just hurt consumers, we hurt the environment with unnecessary waste of electronics, and we hurt the real, quality manufacturers who want to sell good stuff but can't because there's no way to tell consumers "all the other crap on the shelf will break in under two years and we won't" so they end up getting crushed by people who cut corners.
  - benjamincburns 13y ago
    I hope you don't work in UX. "Educating the consumer" is the onus of the manufacturers. It doesn't mean 10-page instruction manuals with 6-point font or hours of meticulous research [edit: this is a horrible way to educate consumers]. In this case it probably means packaging and labeling which plainly states "not for use in recessed fixtures" in a way which most anyone would understand. This could be a sticker which says just that, it could be iconography, it could be an obnoxious DVD on loop in the lighting aisle at Home Depot, or it could be all of those things. Yes, it's a light bulb (a light bulb!) but that doesn't mean manufacturers shouldn't attempt to get consumers to use it properly.
    - Pxtl 13y ago
      If your product requires that you "educate consumers" away from using it in a way that they can perfectly reasonably expect it to work? Your product is defective. A big warning label on the front of the box is the only reasonable accommodation for this, but in the real world this kind of defect ends up in the fine print. If you want to make a special light-bulb that is only compatible with a narrowly defined set of environments, then make your own socket that is only compatible with your bulb and then sell fixtures that provide the needed environment. If you want to use a standard socket, then you have to take the bad with the good and also deal with the kind of environments you'd find. This is the same bullcrap with devices that completely fail to charge on 0.5Watt USB power-supplies. If you can't charge off a standard USB connection, then you shouldn't use a USB port, because USB defines 0.5Watts and your device isn't USB-compatible. Legally required to support USB? Then stop pussy-footing around and actually support it instead of exclusively supporting a 1 or 2 watt perversion of the standard.
crazy1van 13y ago
I doubt customers will react well to their bulbs changing brightness levels on their own.
- bronson 13y ago
  The incandescents in my kitchen change brightness every time the microwave turn on. I can live with it. (It's old knob & tube wiring. Electricians claim it's safe)
  - taybin 13y ago
    Knob & tube is notorious for causing fires. I'd get a second opinion on its safety. http://www.oldhouseweb.com/how-to-advice/knob-and-tube-wiring.shtml http://www.oldhouseweb.com/how-to-advice/knob-and-tube-wirin...
    - danielweber 13y ago
      It's safe.
    - halostatue 13y ago
      Knob & tube left in place is generally safe. If you want to do anything at all with the electrical system, however, you'll need to upgrade the whole system.
    - ars 13y ago
      Knob and tube is safe if enclosed (in a wall, ceiling, etc.). Surprisingly it's actually more safe than new wires! But if exposed and someone can touch it, then it's dangerous.
    - toast0 13y ago
      If it's been oked by multiple electricians, it's probably OK. As your article states, properly installed knob and tube is at least as safe as modern wiring. The major problem is that since knob and tube lost favor and today, demand for electricity within the home has grown considerably, and a lot of knob and tube systems were expanded improperly; this can happen with modern wiring as well. Also, the insulation issue.
trebor 13y ago
Thermistors will help, yes, but the manufacturers need to design better enclosures for LED lightbulbs. They need fair air circulation for that heat sink to work well. And in recessed lighting it's the worst. It's a design issue of the bulb, sure, but especially the fixture. LEDs aren't friendly to high heat like incandescents are, and most light fixtures have been designed with complete disregard to the heat of the fixture—so long as it won't start a fire.
- Florin_Andrei 13y ago
  It's difficult. The CFL has a huge volume and a huge radiating area for the heat, and that area is well-connected thermally with the environment. Plus, it can operate at higher temperatures anyway. The LED active element is a tiny chip of semiconductor material. All that heat is dumped in a tiny volume, and you can only put a heat sink on its back. Plus, the heat sink is close to the fixture and therefore necessarily hampered in its function. It's not an easy problem to solve. If we think pie-in-the-sky solutions, perhaps a re-design of the connectors and fixtures might help - if you made a connector that was designed to take heat away from the bulb, that would help a lot; the whole fixture would become the heat sink.

tl;dr: LED bulbs get too hot, lowering their life expectancy. Manufacturers need to include cheap thermistor circuits, which automatically dim the light to a safe thermal equilibrium.

benjamincburns 13y ago

Consumers need to be educated, too. Anyone using an A19 in a can-style fixture is wasting energy by lighting things they don't need lit. Use something directional like a PAR or a BR, and you can reduce the amount of wattage consumed to light a given area. Further, LED manufacturers design their directional lamps with these applications in mind. See the spiral pattern [1] on the heat sink around Lighting Science PAR bulbs? That's designed to use the thermal differential to create a nice air flow up into the fixture so that it may be used in a recessed or other partially-enclosed fixture. 1: http://www.1000bulbs.com/product/100560/LED-PAR3011HE25WW.html http://www.1000bulbs.com/product/100560/LED-PAR3011HE25WW.ht...

Lightbody 13y ago
It's not that simple, sadly. My house has 100+ canned recessed lights, all of which had been filled with Sylvania 50W Halogen PAR30 & PAR30LN bulbs. I have been desperately trying to find a replacement LED that matches the same warmth and color. This bulb claims to be the exact replacement: http://www.amazon.com/gp/product/B00467E3LA/ http://www.amazon.com/gp/product/B00467E3LA/ But yet this one and others that have similar lumens, temperature, and equivalent watts all don't even get close to the warmth that the halogens produced. Fortunately, I found a cheap alternative: http://www.amazon.com/Philips-424374-7-watt-Household-Dimmable/dp/B00B4CPLGG/ http://www.amazon.com/Philips-424374-7-watt-Household-Dimmab... It's the A19 40W that the article cautions against, and it looks slightly less sexy in the recessed can, but the color almost exactly matches the halogens I have (except when dimmed -- nothing can match the fireplace-like glow). What's weird is that the lumens and temperature for that bulb aren't even close to what the halogens claim, but they look almost identical. Which has made me wonder if this switch to LED is way more complex than just those two measurements :P
- colechristensen 13y ago
  http://www.switchlightingco.com http://www.switchlightingco.com produces excellent (though expensive) LED lights which are, I'd say, 95% of what I could want out of a halogen replacement.
- benjamincburns 13y ago
  > (except when dimmed -- nothing can match the fireplace-like glow). I can't talk specifics (under NDA from a former employer), but this is a problem for which solutions exist. I don't know that manufacturers think there's much of a market there, however. > Which has made me wonder if this switch to LED is way more complex than just those two measurements :P It is. There are a bajillion things going on. One which you've already noticed is how dimming impacts color temperature. CRI is also a huge issue. Then there's the optics - LEDs are very directional, so they require pretty advanced lenses in order to achieve a desired lighting pattern [1]. Optics impact all kinds of things, including color temperature, and since the development cost is high you can expect cheap brands to skimp there. If you're comparing them by looking directly at the bulb, internal glare/reflection is hard to match as well. I'd still caution against using the A19s in a recessed fixture. It's not a safety issue (that I'm aware of), but you definitely won't get the rated life out of the bulb. Out of curiosity, did you try an LED BR30? I think you might find one from a quality manufacturer to be a bit better than the A19. 1: $20 says the lighting pattern on the Sylvania LED is smoother/more regular than the Sylvania halogen, but I'm biased since I know the guy who designed the lens.
- ScottBurson 13y ago
  I just put four of these in my kitchen and I think they do a remarkably good job of simulating incandescent color: http://www.amazon.com/Ecosmart-Powered-Recessed-Light-Dimmable/dp/B004OP84RS/ http://www.amazon.com/Ecosmart-Powered-Recessed-Light-Dimmab...
Pxtl 13y ago
It's a light bulb. A light bulb. This isn't a car, which you expect to require some expertise. It's not a furnace that will be primarily handled by an HVAC specialist. It's a light bulb. Consumers have a reasonable expectation that devices like this Just Work. If the device fails to meet its promised service-level without a dozen asterisks in its usage? It's not meeting its intended purpose and it's defective. Consumers should not have to meticulously research every small purchase. Simple, small purchases of replacement parts should not require reading a 10-page instruction manual of 6-point font, especially since you didn't get this manual until after you got the damned thing home. By allowing manufacturers to sell these defective devices, we don't just hurt consumers, we hurt the environment with unnecessary waste of electronics, and we hurt the real, quality manufacturers who want to sell good stuff but can't because there's no way to tell consumers "all the other crap on the shelf will break in under two years and we won't" so they end up getting crushed by people who cut corners.
- benjamincburns 13y ago
  I hope you don't work in UX. "Educating the consumer" is the onus of the manufacturers. It doesn't mean 10-page instruction manuals with 6-point font or hours of meticulous research [edit: this is a horrible way to educate consumers]. In this case it probably means packaging and labeling which plainly states "not for use in recessed fixtures" in a way which most anyone would understand. This could be a sticker which says just that, it could be iconography, it could be an obnoxious DVD on loop in the lighting aisle at Home Depot, or it could be all of those things. Yes, it's a light bulb (a light bulb!) but that doesn't mean manufacturers shouldn't attempt to get consumers to use it properly.
  - Pxtl 13y ago
    If your product requires that you "educate consumers" away from using it in a way that they can perfectly reasonably expect it to work? Your product is defective. A big warning label on the front of the box is the only reasonable accommodation for this, but in the real world this kind of defect ends up in the fine print. If you want to make a special light-bulb that is only compatible with a narrowly defined set of environments, then make your own socket that is only compatible with your bulb and then sell fixtures that provide the needed environment. If you want to use a standard socket, then you have to take the bad with the good and also deal with the kind of environments you'd find. This is the same bullcrap with devices that completely fail to charge on 0.5Watt USB power-supplies. If you can't charge off a standard USB connection, then you shouldn't use a USB port, because USB defines 0.5Watts and your device isn't USB-compatible. Legally required to support USB? Then stop pussy-footing around and actually support it instead of exclusively supporting a 1 or 2 watt perversion of the standard.

crazy1van 13y ago

I doubt customers will react well to their bulbs changing brightness levels on their own.

bronson 13y ago
The incandescents in my kitchen change brightness every time the microwave turn on. I can live with it. (It's old knob & tube wiring. Electricians claim it's safe)
- taybin 13y ago
  Knob & tube is notorious for causing fires. I'd get a second opinion on its safety. http://www.oldhouseweb.com/how-to-advice/knob-and-tube-wiring.shtml http://www.oldhouseweb.com/how-to-advice/knob-and-tube-wirin...
  - danielweber 13y ago
    It's safe.
  - halostatue 13y ago
    Knob & tube left in place is generally safe. If you want to do anything at all with the electrical system, however, you'll need to upgrade the whole system.
  - ars 13y ago
    Knob and tube is safe if enclosed (in a wall, ceiling, etc.). Surprisingly it's actually more safe than new wires! But if exposed and someone can touch it, then it's dangerous.
  - toast0 13y ago
    If it's been oked by multiple electricians, it's probably OK. As your article states, properly installed knob and tube is at least as safe as modern wiring. The major problem is that since knob and tube lost favor and today, demand for electricity within the home has grown considerably, and a lot of knob and tube systems were expanded improperly; this can happen with modern wiring as well. Also, the insulation issue.

trebor 13y ago

Thermistors will help, yes, but the manufacturers need to design better enclosures for LED lightbulbs. They need fair air circulation for that heat sink to work well. And in recessed lighting it's the worst. It's a design issue of the bulb, sure, but especially the fixture. LEDs aren't friendly to high heat like incandescents are, and most light fixtures have been designed with complete disregard to the heat of the fixture—so long as it won't start a fire.

Florin_Andrei 13y ago
It's difficult. The CFL has a huge volume and a huge radiating area for the heat, and that area is well-connected thermally with the environment. Plus, it can operate at higher temperatures anyway. The LED active element is a tiny chip of semiconductor material. All that heat is dumped in a tiny volume, and you can only put a heat sink on its back. Plus, the heat sink is close to the fixture and therefore necessarily hampered in its function. It's not an easy problem to solve. If we think pie-in-the-sky solutions, perhaps a re-design of the connectors and fixtures might help - if you made a connector that was designed to take heat away from the bulb, that would help a lot; the whole fixture would become the heat sink.