Help with this LED please :)

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300winmag
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Help with this LED please :)

textileRef:128179026261a7524c63d2d:linkStartMarker:“This is a 12v spot light which claims 5000 lumens and 50 watts. When I first hooked it up to my full 12v car battery on my bench I was impressed with the beam but then I noticed a bunch of yellow artifacts and how dim it was. I have a lot of lights and I am 99% sure this light is not 5000 lumens… more like 3000 but I want to be certain.
I inter webbed the snot out of this and according to “ Kangrong Fine Ceramic”:http://en.kangrong.com/product/proList.aspx?node=101004012&pid=6&p2=48 this is a “K905C CREE CXA1816 or 1820” both are not rated for the above lumens or watts and the pictures of the led itself don’t look even close. It looks exactly like a CXA1850. Due to it being an out door spot light(on my vehicle) I would prefer to not open the light so I am hoping you all can help me out here. Is it possible because they are all the same size led that they put in the XLamp CXA1850 into a K905C holder? Or can the CXA1816 and 1820 look like an 1850? Hell it could even be an CXA1830 but again the LED does not look like the one on cree’s website. The only one I found that does is the 1850.

Here are the specs for the CXA1816

Size 17.85 × 17.85 mm
Product Options High-CRI
Maximum Drive Current 0.9 A
Maximum Power 38 W
Light Output Range 1700 – 3800 lm
Maximum Efficacy at Binning Conditions 149 lm/W
Light Emitting Surface (LES) 12 mm
Typical Forward Voltage 36.2 V @ 450mA
Maximum Reverse Current 0.1 mA
Viewing Angle 115 °
Binning 85°C
ANSI (White)
2- and 4-Step EasyWhite®
Maximum ESD Withstand Voltage 8000 V (HBM per Mil-Std-883D)
RoHS-Compliant Yes
REACH-Compliant Yes
UL-Recognized Yes – Level 4 Enclosure Consideration

Here are the spec for the CXA1820

Size 17.85 × 17.85 mm
Product Options High-CRI
Maximum Drive Current 1.05 A
Maximum Power 40 W
Light Output Range 3000 – 4500 lm
Maximum Efficacy at Binning Conditions 140 lm/W
Light Emitting Surface (LES) 12 mm
Typical Forward Voltage 36.2 V @ 550 mA
Maximum Reverse Current 0.1 mA
Viewing Angle 115 °
Binning 85°C
ANSI (White)
2- and 4-Step EasyWhite®
Maximum ESD Withstand Voltage 8000 V (HBM per Mil-Std-883D)
RoHS-Compliant Yes
REACH-Compliant Yes
UL-Recognized Yes – Level 4 Enclosure Consideration

Here are the specs for the CXA1850.

Size 17.85 × 17.85 mm
Product Options High-CRI
Maximum Drive Current 2.1 A
Maximum Power 78 W
Light Output Range 6000 – 9400 lm
Maximum Efficacy at Binning Conditions 123 lm/W
Light Emitting Surface (LES) 12 mm
Typical Forward Voltage 35 V @ 1.4 A
Maximum Reverse Current 0.1 mA
Viewing Angle 115 °
Binning 85°C
ANSI (White)
2- and 4-Step EasyWhite®
Maximum ESD Withstand Voltage 8000 V (HBM per Mil-Std-883D)
UL-Recognized Yes – Level 4 Enclosure Consideration

Edited by: 300winmag on 08/26/2016 - 01:57
djozz
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I have no idea what is going on, but to add to the confusion: around the COB it says 3A and 70V DC. So with 36 dies, it must be wired in 2 strings of 18. And at 3A that should be a 210W COB.

300winmag
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Location: Calgary, Canada

It is an odd story but finding out which LED this is will help me sleep at night Silly

Old-Lumens
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You may remain sleepless. It does not look like a Cree at all to me, but another manufacturer of that style led. None of these manufacturers seem to worry about telling the truth, so it could easily not be a Cree at all. Once you take it apart, you should be able to tell more about the led, because if it is a Cree, there should be markings showing that, on the led. Rip her apart and let's see.tongue-out

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300winmag
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It doesn’t look like the 1850 to you guys? What am I missing?

Texlite
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300winmag wrote:
It doesn’t look like the 1850 to you guys? What am I missing?

Could be a CXA1850, dice look like they match.

Could be they simply reused the ceramic holder, that would be my guess.

Only way to know for sure is to pull it apart, should say Cree under that holder and match the layout. From what little you can see in the pics, like the attachment point for the thermocouple, there’s a good chance it could be a genuine Cree.

That only gets you halfway there though, you’ll still need to measure the voltage and current to know exactly what kind of actual lumens its producing.

Post up a link to the light, I’m genuinely curious.

-Michael