State of the art high power LED

Thread Starter

oz93666

Joined Sep 7, 2010
739
I've just discovered these are available ... super high power , up to 300W , in a very compact size , making them ideal for powerful zoom-able torches or spotlights ....


But my question is what does the white block in the right hand corner do ??? It's described as a "a high quality thermal resistance" ... Is this a cutout if the device should get too hot ??? Leds do not normally have current limiting resistors built in it would restrict usage and limit design ..

Power input is 12V current over 20A!!!

https://www.ebay.co.uk/itm/LED-ligh...hash=item36516a626f:m:mYGvfNLZFe4clwdEi8k5I5g
 

MisterBill2

Joined Jan 23, 2018
18,176
What that "white block" in the lower right corner looks like to me is a connector for the external controller that is not mentioned.The other thing not mentioned is the heat sink that an LED with a 200 watt input will need to have. They do get hot, 12 volts and 20 amps =240 watts power input, and if light out=200watts then that means 40 watts of heat to remove. Not a small challenge.
 

Thread Starter

oz93666

Joined Sep 7, 2010
739
'Thermal resistance" is a term commonly used to describe the ability to dissipate power. I don't really think it has much to do with the white connector.
To me it seems the connector wires are tied to a very small device, probably used to indirectly measure the temperature of the arrangement. https://www.lumileds.com/uploads/568/WP23-pdf
Here's the picture where the component is named ... probably an error in translation could be "high quality thermal RESISTOR " But what is a "thermal resistor" ???

Maybe the white block is a socket for a fan , and the resistor is the small black thing slightly above and to the left?
 

Thread Starter

oz93666

Joined Sep 7, 2010
739
What that "white block" in the lower right corner looks like to me is a connector for the external controller that is not mentioned.The other thing not mentioned is the heat sink that an LED with a 200 watt input will need to have. They do get hot, 12 volts and 20 amps =240 watts power input, and if light out=200watts then that means 40 watts of heat to remove. Not a small challenge.
Ha ... Synchronicity ... we had the same thought at the same time!

But something told me your figure for the heat was a bit low ... A search shows the best leds are only 25% efficient .. so a 200W led needs to dissipate 150W in heat!!
A candle is listed as 0.04% efficient ...florescent /halied around 12% ...incandescent 1.5%

Yes the very best heat sink is essential otherwise it would blow very quick ..


Those are copper tubes ... evacuated with a fluid inside , often water , and a wick ...Heat pipes ....

 
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Audioguru

Joined Dec 20, 2007
11,248
The high power LED sold on ebay, is Chinese and is unbranded so the specifications are just a bunch of lies.
A real Western manufacturer would tell the truth, guarantee it and show how to cool the extremely hot thing.
 

MisterBill2

Joined Jan 23, 2018
18,176
I based my statement on the theory that the 200 watts was the light output, since that was what the claim seemed like to me. Yes, there is a whole lot of heat to be removed, and that certainly looks like a small 2 circuit locking connector, sort of like I have seen in a large screen LCD TV. and that small surface mount block thing could be the good thermistor. So there would be an external controller needed. Probably OSRAM has a recommended control circuit design available, to help them sell more LEDs.

AND, if it really is an OSRAM device it will meet the OSRAM published specifications, no matter where it is produced. But a counterfeit part probably will not meet those specifications.
 
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Thread Starter

oz93666

Joined Sep 7, 2010
739
The high power LED sold on ebay, is Chinese and is unbranded so the specifications are just a bunch of lies.
A real Western manufacturer would tell the truth, guarantee it and show how to cool the extremely hot thing.
Are there any western manufacturers ???

I agree you cannot trust wattage ratings on complete lamps ... I have dismantled many and the power input is often less by a factor of 3 compared to the manufacturers rated wattage ....

But component chips are a different matter ... I have bought literally dozens of different types , and the voltage and current when measured do correspond accurately with the rated power ...

A 200W of the design pictured ( I am confident) will show around 14A at 14V ... total power in 200W total light out 50W ( I've just ordered one from eBay , 200W cost 43 pounds)
 

Audioguru

Joined Dec 20, 2007
11,248
Lumileds (started by Philips) and Osram are well known trustworthy Western LED producers.
A 1W LED is very bright. Why do you want hundreds of Watts?
 

Thread Starter

oz93666

Joined Sep 7, 2010
739
Lumileds (started by Philips) and Osram are well known trustworthy Western LED producers.
A 1W LED is very bright. Why do you want hundreds of Watts?
As you've probably noticed from the second picture on this thread the led chip itself is Osram ... But the only sellers of this item I've found are on Ebay and alibaba , based in China .. it appears the manufacturer is Chinese ....

from wikipedia .... Osram's headquarters is in Regensburg, Germany, it has further production sites in Penang and Kulim, Malaysia, and Wuxi, China...

I think western companies are pioneers in innovation and design , but mass production is cheaper in China ...

Generally we must be cautious of unbranded Chinese goods , but when a product has a long established history , Chinese owned companies are OK .... A good example of this is solar panels ... the market is massive and they have now been produced for decades , the process is fairly simple and manufacturers in the West use the same standard machinery to produce them that Chinese companies do... Of course Western companies cannot produce as cheaply , so all they can do is repeat the mantra "beware of cheap inferior Chinese products" . This may work on the ignorant public , but bulk buyers know there's no truth in it .. so Western politicians put on import taxes.
 

Audioguru

Joined Dec 20, 2007
11,248
Why is the Chinese product with the Osram rejects on it labelled "unbranded"?
Are the Osram parts genuine or are they fakes that look the same?
 
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MisterBill2

Joined Jan 23, 2018
18,176
Lumileds (started by Philips) and Osram are well known trustworthy Western LED producers.
A 1W LED is very bright. Why do you want hundreds of Watts?
Driving lights and illuminating a large area come to mind as applications needing much more power. And also to scare off the "bad guys", a super bright light is fairly effective and far safer than shooting at them, and it does much less damage as well.That is another good reason.
 

Audioguru

Joined Dec 20, 2007
11,248
Chrysler cars, trucks and Jeeps use high beams as daytime running lights to blind oncoming drivers. Lately VW and Kia copy them.
They do not use hundreds of Watts.
 

MisterBill2

Joined Jan 23, 2018
18,176
The US Army is also using intensely bright lights as a weapon of some kind. I read about it in "Stars and Stripes". The details were not given, though. And automotive headlights are not nearly as bright as some other ones.
 

Thread Starter

oz93666

Joined Sep 7, 2010
739
The US Army is also using intensely bright lights as a weapon of some kind. I read about it in "Stars and Stripes". The details were not given, though.
Absolutely ... particularly for blinding ... In the movie 'men in black' the flashy thing is totally feasible ... I don't know for memory wipe , but certainly for blinding ... for a short pulse there is no need for a heat sink , this is the main bulk ... A small device as in the movie could deliver 10's of KW for a few milliseconds ... enough to blind anyone looking at it 10 meters away ...
A long range weapon is also easy with lenses , probably able to permanently blind up to a Km , the people would have to be looking roughly in your direction.

The high power light in this thread would not be used for normal high power lighting needs , normal chips can do that and only cost a $ for 100 W ....
the thing about this led chip is the light is emitted from a very small area , essential for spot lights and focusing touches ... the smaller the light emitting area the more parallel the beam can be made , using a lens ... A compact high power led is not easy to achieve , the vast amount of heat must be dissipated or the led will blow. ,
 
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