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  • DanKegel
    replied
    Originally posted by azdave
    White LEDs were originally easiest and cheapest to produce in the blue-white color range (5000K). They create white light through the process of luminescence. All white LEDs are actually blue LEDs that excite a phosphor layer surrounding the die to produce what we peceive as white light. As the production of white LEDs have evolved, the manufacturers have been able to modify the phosphor layer to get a uniform warmer white light that better simulates a traditional filament bulb.
    Yeah, it does seem like blue-white was easier to make, and they've been struggling to achieve that 'warm' look of traditional bulbs.
    wikipedia.org/wiki/Light-emitting_diode#White says there are several ways to achieve white LEDs.
    Cree used to offer a "TW" bulb that used neodymium glass to achieve higher CRI (color rendering index) at the cost of lower efficiency. I think they stopped doing that a few years ago.

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  • azdave
    replied
    Originally posted by DanKegel
    LEDs are more sensitive to heat than the CFLs somehow.
    The heat is concentrated in the driver base, not distributed over the emitting surface, I thinkW equivalents, they're overkill most of the time (and more expensive?).

    Be careful to get the right color temperature.
    For some reason, it's easy to accidentally get a more sunlight-y LED than it was with incandescents.
    LEDs thrive on cold temperatures and have high output when cold. The lumens output is reduced at higher temperatures and if they can't reject enough heat from the die junction it significantly shortens the service life. While it's true LEDs are more efficient than many other lighting types there is still a small percent of energy converted to heat and that energy builds up quickly. It has to be dealt with using heat sinks. In some automotive LED headlamps they use small cooling fans to prevent overheating.

    White LEDs were originally easiest and cheapest to produce in the blue-white color range (5000K). They create white light through the process of luminescence. All white LEDs are actually blue LEDs that excite a phosphor layer surrounding the die to produce what we peceive as white light. As the production of white LEDs have evolved, the manufacturers have been able to modify the phosphor layer to get a uniform warmer white light that better simulates a traditional filament bulb. Many people find the warm light less harsh to the eyes.

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  • DanKegel
    replied
    I trust Bruce knows what he's doing, looking forward to hearing what ends up working for him.

    LEDs are more sensitive to heat than the CFLs somehow.
    The heat is concentrated in the driver base, not distributed over the emitting surface, I think.
    Unless you've tried a lower wattage and found it lacking, avoid the 100W equivalents, they're overkill most of the time (and more expensive?).

    Be careful to get the right color temperature.
    For some reason, it's easy to accidentally get a more sunlight-y LED than it was with incandescents.
    If you like warm light, e.g. for living spaces, 2700K is the right one.
    Higher temperature like 3000K (or even 5000K) are brilliant bluish sunlight, good for work areas.

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  • SunEagle
    replied
    Originally posted by bcroe

    I just figured that 100W equivalents running an actual 15W would be way cooler than the original incandescent. I
    kind of like 100W or 75W, the 60s and down used to seem so much dimmer. Bruce Roe
    I just replaced a 22 watt CFL with a 60 watt equivalent LED (i think it is rated about 10 watts). The LED is much brighter and is white in color compared to the CFL.

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  • bcroe
    replied
    Originally posted by DanKegel
    100W equivalents are hot, rare beasts around here, I don't use them much. I would be
    careful with enclosed fixtures, not many LEDs are rated for use in them, too hot.
    I just figured that 100W equivalents running an actual 15W would be way cooler than the original incandescent. I
    kind of like 100W or 75W, the 60s and down used to seem so much dimmer. Bruce Roe

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  • DanKegel
    replied
    I find 40W equivalents from major brands to be as bright as 60W ceiling fan bulbs. (Maybe they're rated so they stay at least 40W equivalent as they dim towards end of life?)
    My rooms tend to have multiple sconces on the walls, so those 40W ones are great.

    I use 60W or occasionally 75W equivalents for stubborn rooms that need lots of light.

    100W equivalents are hot, rare beasts around here, I don't use them much. I would be careful with enclosed fixtures, not many LEDs are rated for use in them, too hot.

    I've had about 4 crees fail out of about 75 in a couple years, mostly new models before they worked the kinks out. Not bad. Of a dozen or so Philips and Sylvania, no failures so far.

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  • bcroe
    replied
    The idea is a centralized light for the room, as much as the fan; I don't care for lamps exclusively. The fans tend
    to take regular screw in bulbs; that could be modified. The so called "equivalents" tried before were not nearly
    bright enough; guess I'll go for 100W LED equivalents (15W) for now. Some fixtures have lamps exposed; some
    with a glass cover, and the radiation angle of the LEDS varies too. I think it will be necessary to try each setup
    in a "test" position for effect before final installation. Bruce Roe

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  • SunEagle
    replied
    Originally posted by DanS26

    I have mixed experience with LED's.........

    Burn out quickly with the Cree
    Buzzing with the Phillips and Hykerion
    Delay lighting with the Westinghouse in cold climate.

    Seems to me the tech is still in process.
    The only short life bulbs I have had were 4W no name brand with MR16 based used in ceiling cans. They were cheap and a couple did not last long.

    I also have delayed lighting on some 24 watt down lights that I installed 8 yeas ago. They were early versions of LED but still put out a lot of light.

    I have a mix of LED's from 2 watt candelabra, 4watt MR16 base, 6 watt A19 base, 2 foot 10 watt to 4 foot 18 watt type that replaced my original fluorescent and a couple of other types mixed in. I have been using some of them for as long as 8 years and except for the couple of really cheap 4 watt ones they are all still working with little to no side effects like buzzing.

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  • RedDenver
    replied
    I've had good success with Cree. One bulb died after about 10 months, and they mailed me a replacement when I told them online.

    Leave a comment:


  • DanS26
    replied
    Originally posted by SunEagle

    Surprisingly there are a lot of quality LED lamps being made by Philips, Sylvania and Cree. You can find them at the big box stores or Amazon.
    I have mixed experience with LED's.........

    Burn out quickly with the Cree
    Buzzing with the Phillips and Hykerion
    Delay lighting with the Westinghouse in cold climate.

    Seems to me the tech is still in process.

    Leave a comment:


  • SunEagle
    replied
    Originally posted by bcroe
    More energy plans afoot here; one part is room lighting. 4 rooms that had no overhead central fixture
    already have conduit in place with a heavy duty mount for a ceiling fan. Fixed a couple broken fans, now
    have enough fans for every position. The question is, what sort of light should they have?

    Most ceiling fans just had 3 or 4 smaller incandescents sticking out from them. For this high use indoor
    ap, I am thinking going to LEDS might be good. None of those failing, RF generating, fire hazard, curly
    flourescents please. Perhaps adding RF filters would be part of the project anyway, but I'm looking for
    advice on up to date LEDs here. Bruce Roe
    Surprisingly there are a lot of quality LED lamps being made by Philips, Sylvania and Cree. You can find them at the big box stores or Amazon.

    Leave a comment:


  • DanKegel
    replied
    I've had good luck with LEDs from big box stores. There are nice small ones from Philips, for instance.

    The only pain has been dimmer compatibility, it's hit or miss. And it's hard to find good small frosted LEDs for some reason.

    Leave a comment:


  • bcroe
    replied
    More energy plans afoot here; one part is room lighting. 4 rooms that had no overhead central fixture
    already have conduit in place with a heavy duty mount for a ceiling fan. Fixed a couple broken fans, now
    have enough fans for every position. The question is, what sort of light should they have?

    Most ceiling fans just had 3 or 4 smaller incandescents sticking out from them. For this high use indoor
    ap, I am thinking going to LEDS might be good. None of those failing, RF generating, fire hazard, curly
    flourescents please. Perhaps adding RF filters would be part of the project anyway, but I'm looking for
    advice on up to date LEDs here. Bruce Roe

    Leave a comment:


  • SunEagle
    replied
    Originally posted by bcroe

    ANYBODY could do that! The goal here is always to engineer the most efficient design possible,
    to help justify maximizing creature comforts. Bruce Roe
    +1. I agree with you on that plan.

    Leave a comment:


  • bcroe
    replied
    Originally posted by SunEagle

    You can always go old school and do the "manual" door opener.
    ANYBODY could do that! The goal here is always to engineer the most efficient design possible,
    to help justify maximizing creature comforts. Bruce Roe

    Leave a comment:

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