LED hacking of COBs

Ok so I have 500 of these bulbs

They have these 17w 3000k LEDs in them

As you can see the boards are sealed in silicone( probably not actually silicone as it didnt feel that way)
And are a pain in the ass to clean up but I can access both sides just fine for doing modifications to wire lengths and banking them. My question for any of you who have done any of this is can I hook these up in parallel and run the chips like a strip is this worth messing around with?

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What I’m seeing…

The power supply you chipped from the solid covering is only converting the household current (110 AC) to the 30-50 volts DC and current the COB wants to reach that 17W output.

If you take the COBS out you could wire them up in series or such with a different DC power supply that would give a higher or lower current level.

The real question is…
Are the COBs mounted to a heat sink of any kind?
The plastic (assume it’s plastic) housing looks like it is supposed to funnel the air flow in some manner.
The harder you run these the hotter they get, but it you have enough you can run them at half current or less and just keep adding more (raising the voltage to dangerous levels)…

On the other hand…
With that many, anything you do to avoid buying a matching number of screw in sockets is going to be cheaper and easier to wire…

Buzz ON…

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What Halfbee is saying is bang on.
You will need some basic heat-sinking if you try pushing these past 5 watts or so.

Cheers
G

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The casing they were in is aluminum they were mounted with thermal paste. I plan on mounting them to aluminum strut. I am a shop manager at a demolition company. As a result I have access to some of the coolest junk you can imagine. Anyway gunna play a bit and post my findings.

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depending on spacing any stock .150 and up will be good. I’d go for angle for the rigidity.

Cheers
G

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Proof of conconcept I’m actually reading these chips as 31v and .946 amps hooked up 2 leds 2 one chip let’s see what else we can do. Keep in mind I’m just playing with them.for now gunna go strip a few more apart see what I can rig up

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I harvested 10 leds and the thermal paste I removed the tbsp on the little plastic retainers so I can reuse them to fit onto the aluminum frame I made. Removed the chips I didnt completely remove the ends yet because I want to see what I can do with 1 maybe 2 chips

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Basically as far as I will get tonight gunna add another chip now

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With 2 chips

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I hope you got those bulbs for free. Otherwise this whole endeavor is a waste. Even if you spent 1$ a piece you could build a decent 1000 watt lm301b light with 500$.

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They’re free there is no cheaper than this I am also just playing around with them

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Well I’ve fiddled with different combinations of series and parallel to try and discover if I have CVD or CCD I dont seem to be drawing a difference as far as brightness but it seems my drivers are constant current amps are the same constantly and the voltages are fluctuating

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Which seems brighter to you

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The first although the second may be warmer. I have seen bulbs for sale that change the color rather than the intensity when dimmed.

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I think that is just camera adjusting

I’m experiencing a voltage fluctuation of .3 volts and its causing a flicker. It is intermittent

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After extensive effing around I figured out that the strip I made in series is slightly brighter than the one in parallel

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That’s good but remember that each one you add to the string ups the voltage by 31v or
so by earlier measurement given. Don’t remember what the lethal level was but personally
don’t like to mess with over 200 volts…

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hmm why’s that?? my HLG driver is 230v max

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They say it’s the current that kills you, not the voltage (that just hurts).
A 100 mA will do the job if it passes through the heart (one hand to the other).
I knew a guy that said he preferred working 550VAC instead of 230 - he said “you don’t stick to 550”. I personally saw him thrown 15 feet from a bus-bar panel - get up and go back at it again. :face_with_symbols_over_mouth:

Cheers
G

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