75 watts of light and only uses 7.8 watts

LEDBE
Yeah, that's pretty bad math or advertising. It's more like a 40 Watt Incan.

I'd like to see the calculation they used to come up with that. It seems to me like some guy was sitting there, did the math, and then went 'beh, that sounds lame, no one will know if we double it'.
 
I have seen a lot of "bad math" when it comes to LED household lamps in stores. When the CFL replacements came out the math wasn't great either but it has gotten more equal. I don't pay attention to the wattage equivelents much I always look at lumens.
 
Claiming "75 watts of light" implies that you are in fact emitting enough light to equal 75 joules per second of light - 4.2 joules of light will heat a gram of water 1 degree C. This is a lot of light, as white LED light is (depending on several things like dominant spectra and such) about 300 lumens per watt. So about 22500 lumens - not so shabby! But nobody can make "75 watts" of light by consuming "7.8 watts" of power. It's false on the face of it.

If you stretch and say "Output equivalent to a 75 watt lightbulb," then we have to reference output of 75 watt bulbs, which are about 1300 lumens. If the LED claimed emits 1300 lumens (with about 10% optics losses factored in) while consuming 7.8 watts, it has an astonishing 167 lumens per watt efficiency. This is slightly more efficient that Cree's best LED does in lab conditions, but at 22 times the current.

They claim 470 lumens for this LED - while that's not bad for a CRI of 90 at varying color temperatures, it's really got about the output of a 30 watt incandescent bulb. So it's not a bad LED edison fixture, considering that all LED edison fixtures start out bad. Buy real LED lights that aren't crammed into a tiny insulated appliance in the first place!
 
Is it possible that most folks don't need 1130-1300 lumens from each fixture?

Maybe 450-540 lumens that are directed to the intended area are better than 1200ish lumens going everywhere?
 
AnAppleSnail said:
Claiming "75 watts of light" implies that you are in fact emitting enough light to equal 75 joules per second of light - 4.2 joules of light will heat a gram of water 1 degree C. This is a lot of light, as white LED light is (depending on several things like dominant spectra and such) about 300 lumens per watt. So about 22500 lumens - not so shabby! But nobody can make "75 watts" of light by consuming "7.8 watts" of power. It's false on the face of it.

If you stretch and say "Output equivalent to a 75 watt lightbulb," then we have to reference output of 75 watt bulbs, which are about 1300 lumens. If the LED claimed emits 1300 lumens (with about 10% optics losses factored in) while consuming 7.8 watts, it has an astonishing 167 lumens per watt efficiency. This is slightly more efficient that Cree's best LED does in lab conditions, but at 22 times the current.

They claim 470 lumens for this LED - while that's not bad for a CRI of 90 at varying color temperatures, it's really got about the output of a 30 watt incandescent bulb. So it's not a bad LED edison fixture, considering that all LED edison fixtures start out bad. Buy real LED lights that aren't crammed into a tiny insulated appliance in the first place!
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But I thought my 250hp car motor made 1000hp. You mean that can't be true either?
 
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Why the Array LED bulb? ----- See for yourself

Buy the bulb and try it, you will see it's as bright as a 75 watt incandescent, it sure works for me.

I'm most impressed with this LED bulb, I have tried dozens of others including the cheap ones from China and Cree all of which runs very hot , the Array is by far the best of breed. It's sure got Cree beat all to hell:)

The Array LED uses very low power, no heat and is fully dimmable on any standard dimmer.

All the other LED's I have seen were like having a big heat lamp, that's a big waste of power. The NEXXUS Array LED does not run hot and uses less power to produce more light.

All I can say is try it, buy one and try it, you will see for yourself. I want to hear a review from someone else. And when you do buy one and try it, PLEASE e-mail me and tell me what you think.
http://www.greenlightingsupply.com/Array_Lighting_Dimmable_LED_PAR30_Med_Base_Lamp_p/napar30.htm

Why the Array LED bulb? READ THIS
http://www.arraylighting.com/why-array/
 
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AnAppleSnail said:
Claiming "75 watts of light" implies that you are in fact emitting enough light to equal 75 joules per second of light - 4.2 joules of light will heat a gram of water 1 degree C. This is a lot of light, as white LED light is (depending on several things like dominant spectra and such) about 300 lumens per watt. So about 22500 lumens - not so shabby! But nobody can make "75 watts" of light by consuming "7.8 watts" of power. It's false on the face of it.
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This sounds almost exactly like something I wrote in another thread. I hate the term "watts of light" with a purple passion. It has to be one of the most meaningless, confusing, and imprecise terms that ever existed. Even if you assume "watts of light" means incandescent bulb equivalent, not all incandescent bulbs are equal. Some 75 watt lamps emit about 1200 lumens. I've also seen ones which emit 700. And lower wattage bulbs always have lower lumens per watt, making the term even more nebulous. In short, if someone say "100 watts of light", and it's taken to mean incandescent equivalent, then you could mean as high as 3500 lumens ( i.e. short-life 100 watt projector bulbs ), or as low as 400 lumens ( 25 4 watt night light bulbs ). That's close to an order of magnitude difference! Simply put, "watts of light" is a term which should be relegated to the dustbins of antiquity.

Also, the math they're using for the lifetime is suspicious:

Each Array bulb will cost much more than its glass and filament 60W incandescent ancestor, but a lifespan of some 50,000 hours ( three years permanently lit, or about 10 years or so of "normal" use) combined with the electricity savings you'll make, will compensate for the price.

50,000 hours is 5.7 years permanently lit, not 3 years. No idea what "normal use" is, but if you assume 8 hours per day, then that's about 17 years.
 
Re: Why the Array LED bulb? ----- See for yourself

easytim said:
Buy the bulb and try it, you will see it's as bright as a 75 watt incandescent, it sure works for me.
/
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Well now you're claiming something completely different, technically. Either way, sounds a lot like bad advertising to me.

jtr1962 said:
Also, the math they're using for the lifetime is suspicious:

Each Array bulb will cost much more than its glass and filament 60W incandescent ancestor, but a lifespan of some 50,000 hours ( three years permanently lit, or about 10 years or so of "normal" use) combined with the electricity savings you'll make, will compensate for the price.

50,000 hours is 5.7 years permanently lit, not 3 years. No idea what "normal use" is, but if you assume 8 hours per day, then that's about 17 years.
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Not even suspicious, just plain bizarre.
 
I'm a retired electrician, I have been playing with LED's for a little more than 4 years now.

I have nothing to sell, its not an ad

Try it and see for yourself, buy yourself one 8 Watt LED Array bulb



How about this one ----- the 2.6 watts Array LED bulb replaces a 35 watt halogen bulb, I also own this one.

It's simple, unscrew the halogen and put in the 2.6 watt Array LED. Stand back and have a look for yourself, ask your friends if they can tell the difference. You don't need to do the math to see the difference either, thats some arm chair idea.

Seeing is believing



.
 
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I dug around and believe I found the Array bulb in the Department of Energy's Caliper testing. The bigger PAR 30 bulb spec'd out at 468 lumens for a total of 59 lumens per watt. This might not seem like much, but it's near the top of the performance curve, and extremely good considering it was 2900 CCT. It might be pricey, but it's specs indicate it's hardly a dog, and roughly equivelant to a 50watt R30. A neutral or cooler version should be more efficient.

However, the latest Caliper round also shows what I believe is the $20 Ecosmart sold at Home Depot. This bulb spec'd at 394 lm for 67lumens per watt at around 3000 CCT.

So, while the Array bulb that EasyTim is promoting has an interesting design and has good efficiency, it's a lot more expensive than the more efficient Ecosmart and only a tad brighter.

One thing that does intrigue me though is the Array bulb has a much larger heat-sink per similiar wattage, and this has to translate into some kind of longevity benefit.
 
NICE report Blasterman, The $20 Ecosmart is sold at Home Depot. I one thing I don't like about that is than it reminds me of the LED, It's that super cool white LED light that we see so much of with the Cree led and the fact that it gets so hot. Producing all that heat is a waste of energy.

The Array LED is an exact match in color and it's only warm to the touch. This match in color might not seem important, but it is very important when you have clothing on display in a store or other things displayed like paintings, thats where color means everything.

In normal use like in a child's bedroom, he will be in college when it needs replacing. You know it's paid for itself may times over by then. It's truely a green thing of the future, it contains no mercury like the CFL's do. All we really need now is for the price of the LED to come down in price, for those who really want to go 100% green, your time is now.

I remember the Microwave was $800.00 I seen one in Wal Mart last year for $29.99 I remember the VCR was $1100.00 I remember the DVD $500.00 At the Micro Center computer store last week I seen -A complete computer with Microsoft Windows 7 Professional (64-bit) Intel Pentium Dual Core Processor E5400 320GB 7,200RPM Hard Drive and 2GB DDR2 RAM for just $399.99 The point is the price will go down and without the mercury of the CFL
 
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There was only a negligible difference in CCT between the two bulbs in the DOE test, and the standard Array bulb certainly doesn't have a better CRI than an Ecosmart at the same color temp. This doesn't mean though that you were comparing a different Ecosmart variant with an Array bulb with a more preferrable color temp. The fact we aren't talking about wretched cool-white performance to suit the Cree fan-boys is refreshing enough :)

Still, both bulbs claim 50k hours, and given the similiar wattage the much larger Array bulb would seem to have a bigger advantage in this dept.
 
All we really need now is for the price of the LED to come down in price
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The Ecosmart costs $20, and while I'd like to be skeptical of it's rated lifetime given it's much smaller heatsink, the fact remains it got Caliper certified while the Array didn't.

Also, one disturbing note with the DOE Caliber testing is it seems that LED retrofit performance has reached a performance zenith, if not declined a bit. Unless somebody comes up with a miraculous way to produce hyper efficient amber and red light with current LED technology without producing lots of heat were not moving ahead for awhile. I do give the Array lots of kudos though for trying something different and legit. It just proves once again that the technology is decent - it's the legacy bulb formats that are the problem.
 
easytim said:
This LED bulb gives 75 watts of light and only uses 7.8 watts of power


http://www.led-guy.com/



.
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I can talk about these lights. We own, geez, maybe 30 of them? Possibly more.

First of all, we got them because we needed CIE of 6500K. These lights deliver. We also needed them to be dimmable- and they do (sort of) deliver there- but the control range is very poor and they flicker something awful.

That pretty shroud around the outside? Plastic. Yep that is not metal. The LEDs themselves are 5mm round ones with fat metal leads (to conduct heat?). I don't know- we don't run them full out. I see they've updated their literature to reflect the changes.

The ones we got were supposed to be doped with quantum dots so we could better approximate 6500K. I haven't seen the spectra (and the guy that did it is on vacation) but he tells me it was much better than the other lights we've looked t.

Overall- and we haven't measured the power yet (I can't get anyone to let me buy a Kill-a-watt under contract) they're nice lamps... but useless as dimmers. They do a decent job of wall washing, and so far the CIEs haven't shifted.
 
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