new(?) Sylvania LED bulbs

I was at Lowe's yesterday and noticed a bunch of Sylvania LED bulbs I haven't seen before. The 40, 60 and 75 watt versions were available in 2700 or 5000k and the 100 watt version was available in 2700k. The 40, 60 and 75 were A19 size and the 100 was A21. Price for the 60w versions was 10.97 for the 5000k and 9.97 for the 2700k.

Some information from the box:
8.5w
800 lumen
dimmable
can be used in damp locations - not to be directly exposed to water/weather
do not install in fully enclosed fixtures
5 year warranty

Testing with my cheap, inaccurate meter says it uses 12w vs 10w for the Cree 60w equivalent 5000k. It has a plastic dome unlike the glass one Cree uses. I noticed no noise or flickering when using it on a dimmer. It does seem like it dims down more than the Cree does. I haven't tried pulling it apart to see what it looks like inside. It does direct like straight out the end unlike the Cree.

Cree:


Sylvania:


It is shorter than the Cree and weighs about 1/2 ounce more.

The new style Sylvania LED bulbs were just announced at the end of July

https://www.sylvania.com/en-us/news...es/OSRAM-SYLVANIA-Reinvents-the-LED-Bulb.aspx

Ibought a set of these recently. I purchased the cool white version because I'm tired of the excessively warm CFL's that the power companies are sending out here. These are way too cool. Much cooler than my zebralight SC62d. The thing that surprises me is there is no heat sink on this bulb. I'm assuming they're using a form of thermoregulation to prevent burnout.

You can have any tint you'd like as long as it's blue or yellow


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Erik1213 said:

Ibought a set of these recently. I purchased the cool white version because I'm tired of the excessively warm CFL's that the power companies are sending out here. These are way too cool. Much cooler than my zebralight SC62d. The thing that surprises me is there is no heat sink on this bulb. I'm assuming they're using a form of thermoregulation to prevent burnout.

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I would assume that they are using people's faulty memories in the hopes that no one will notice that it went bad only a couple of years after it was purchased.

At ~95 lumens per watt and 8.5w they can get buy with less heatsinking. There is probably a lot of aluminum under the plastic cover and the plastic is a better backbody radiator than the bare aluminum. I have some LED bulbs where the screw base gets warm as if they are trying to sneak a watt or two of waste heat out that way.

JohnR66 said:

At ~95 lumens per watt and 8.5w they can get buy with less heatsinking. There is probably a lot of aluminum under the plastic cover and the plastic is a better backbody radiator than the bare aluminum. I have some LED bulbs where the screw base gets warm as if they are trying to sneak a watt or two of waste heat out that way.

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I think that the statement "There is probably a lot of aluminum under the plastic cover" is nothing more than unfounded speculation.

I think that the statement "the plastic is a better backbody radiator than the bare aluminum" is similarly just wishful thinking. Blackbody radiation isn't much of a factor at the low temperatures that LEDs should be running at, and I've never seen plastic used as a blackbody radiator. Perhaps you can provide some reference that indicates otherwise?

There are plastics that are designed to be thermally conductive and therefore better at convective cooling than plain plastic, but even these are significantly worse than aluminum.

I picked up three of these bulbs (800L version). Light distribution (by eye) is excellent. It uses a pentagon aluminum tower with the PCB folded down over it and adhered. 24 smd LEDs in all. Bulb dims down well with minimal buzz. Power draw at 122v is 8.8 watts and PF of .93. The white area between the base and dome is actually painted aluminum. The 5000K bulb is $6 and the 2700K bulb is $5.



Steve K. I've seen demonstrations where a fairly thin plastic layer over bare aluminum would improve emissivity and allow for better cooling. Of course, the materials would have to have a thermal compound to improve transfer. Clear to see with a FLIR camera. I'll have to see if I can dig up the link.

Nice that there isn't a black hole in the light distribution at the top of the bulb.

JohnR66 said:

I picked up three of these bulbs (800L version)....
The 5000K bulb is $6 and the 2700K bulb is $5.

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For $6 and $5 WHERE???!!!

Nice answer to Cree's "black hole in the top" lamp, although still CRI of 80.

Someone please make a 4000K flavor!!! I like the Cree bulbs but may try these out of curiosity.

markr6 said:

Someone please make a 4000K flavor!!! I like the Cree bulbs but may try these out of curiosity.

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This is also driving me crazy. Is there a reason no one is focusing on this? This is the main thing holding me back from upgrading to LED right now. I find 3500-4000k to be the perfect kind of white for my tastes.

Will someone please split the 2700-5000K difference?!?

MichaelW said:

Will someone please split the 2700-5000K difference?!?

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I always see the demo at home depot where they have "soft white" "bright white" and "daylight"...but I don't think they have any bright white (neutral) LEDs. I never looked closely but can only assume there is a CFL in that one (or all of them for that matter). The neutral white in that display is just perfect...actually "white"! BTW the daylight where I live still isn't blue.

Hopefully a 4000K LED will become more common soon, and especially in a 100w equivalent! HD used to carry the 100w Swtich in 4000K, but it was very expensive.

I'm just getting into LEDs for the home and I picked up some CREEs and just picked up the new Sylvanias after seeing this thread. The CREEs were ok except for the "light ring", since the LEDs are around the center, I could clearly see the dark top and even the dark area by the base, when placed in fixtures that have the whole bulb visible. The Sylvanias, it's really early to tell but I like those much more better than the CREEs. Time will tell but if I had to guess, I'm betting the new Sylvanias will eat the CREEs market share big time. Having two side by side visually is no comparison. Sylvanias stood out, I can't see why anyone would consider the CREEs, except for longer warranty.

I found the bulbs to run quite hot. 80 Deg C on the metal heatsink area between the base and globe. I measured this with a thermocouple and a dab of thermal grease. Measured base down in an ordinary table lamp. Modern LEDs of good quality can handle this (Cree CXA1304 LEDs will take 105C case temp at 450ma and have minimal fading after 36,000 hrs according to their LM80 datasheet). I'm more concerned about the filter cap longevity.

When I measured with my cheap IR thermometer, I noticed very little difference between the CREE and the Sylvania. I'll see how the reliability is over time.