LED Lighting projects

amberwolf

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EDIT: thread has mutated a bit into LED COB projects, as these are much cheaper than trying to work out a ballast solution for CFLs, starts a few posts down.


So...Lowe's has a good deal on these 65w "4500 lumen" 6500k (bright blue-white) CFLs, at less than $3 each:

https://www.lowes.com/pd/Utilitech-65-Watt-65W-T4-Mogul-Base-Daylight-6500K-CFL-Bulb/3465452

But they require a ballastd that is *not* a regular tube-style ballast, because of a "bypass capacitor" that's already built into the CFL base. Perhaps if this is removed, I could then use the CFL with a regular ballast...but I haven't tested this yet (because this capacitor, from what I've found so far, is chosen to be tuned with the CFL tube, and the one already built into a typical ballast is not the right value for the CFL.

I don't know that these are true, but they probably are. I havent' yet done the experiment to verify, but I probably will if there arent' any cheap solutions otherwise. ;)

So far, the only ones I've found that I'm certain will work with them are the entire $40 (and up) "barn light" fixtures (which include the bulb...so I wouldn't need the separate ones). I can't locate them again now, but I found a few that supposedly work with them, but are basically the same price as the whole fixture (more with shipping), and I can't be certain that they work.


Is there anyone here that has specific knowledge of these, or enough knowledge of ballast operation/etc., to help determine if I might be able to make a regular ballast run these things. I have a few ballasts to experiment with, one modern "dead" unit that I can open up and de-pot, a modern working one, another modern probably-working one (though it doens't light the fluorescent bulbs as brightly as one of the two really old kind do, but it does work with a pair of LED replacments), and a couple of really old ones in an ancient fixture that lights one of the sheds, not counting the modern ones in the five modern fixtures I have lights in that I'm using.

The reason is that they're bright, small(ish), and cheap, and I need a lot of light(s), both for the yard itself, and for work areas, as it's getting harder for my eyes to focus on things I'm working on.

I have one of those greenish-light metal halide barn lights for a yard light now, but something is failing in it. Could be the ballast or the bulb, it shuts off and turns back on every so often. If I can make one of these CFLs work, very cheaply, I can replace the guts of the fixture with the CFL for whiter and possibly brighter light (that uses less electricity, as a bonus).

Then I can use others to light sheds, other yard areas (the trees limit how much of the yard the barn light can illuminate), and rooms in the house if I can do enough of them.


Cheap shop lights with equivalent lighting in fluorescent takes two shop light fixtures and four bulbs, which costs around $50. These are better for some use cases, but it's a lot of money. So a cheaper solution that's just as effective is better. ;)

I expect it's either not possible or more trouble than it's worth, too much time (of which I have too little already), but thought it might be worth at least investigating.
 
marty said:
LED bulbs are about $1 each.

Not for the amount of light I need (4000-5000 lumens per small lighted area, minimum, twice that for some), at the color temperature I need (6500k), including the fixtures to put them into. I'd have to buy sockets, wires, switches, or fixtures that include all those, which is all stuff that I'd have to buy for the other option but I"d get many times the light out of each socket/bulb/switch/fixture for the stuff I am talking about in the first post.

From the looking around I've done so far (not counting random Chinese vendors I can't tell what they're actually selling), even the $40 barn light fixtures would be cheaper for the light I get than "$1" LED bulbs (or any other $1 lights).

I've seen (and got) a few $1 LED lights, and they tend to be "40w equivalent", maybe 200 lumen at the brightest (some only half that), and that's claimed, dunno actual. Color temperature is usually dim yellow, 3000k or less. Not useful to me, as it takes at least several times the amount of lumens of low color temperature light to help me see anywhere near as well as the 6500k light.


There probably isn't any cheap solution to my problem.... :(
 
These are the bulbs in question:
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and this is the bypass capacitor referred to
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This is the box, including the "specs"
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I noticed one of my regular ballasts is very light compared to the others; turns out it either missed the potting process or this model doesn't come potted like others I've seen by this brand. Which is a good thing, because it made it really really easy to open it up and get a peek:
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Looks like the problem with it is a bad capacitor, swollen up. Might also have other issues, but that can be replaced to find out. (this ballast does startup fluorescents, though they never get as bright as they should, but it runs LED tubes normally).

Now...if I can determine what to change (or remove) for the ballast's built-in bypass capacitor, it may then work, at least well enough for a test, with the 65w CFL. I would guess that these are, as they are on the output red and blue wires:
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The rest of these pics are of the present yard lighting, which includes the halide greenish barn light
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a pair of LED downlights that I got at goodwill, socketed into a conduit-type box with a coverplate that has a light sensor to turn them on only when it's dark; they are by the gate and shine into that area of the yard.
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These are a pair of "300 lumen" CFLs in what's left of a no-longer-motion-activated security light (electronics died a long time ago) that light the area under the canopy in front of that shed. Presently they are wired to turn on along with the LED floodlights over the shed south of it, and the halogen floodlights on the front of the shed to the north of it (which don't provide much light for the 300w of power they use up).
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The lighting for the inside of the shed with the LED floodlights over it, which is a single-bulb fixture with an ancient transformer style ballast that has no plastic holders on teh ends anymore, so I ziptied the bulb to the fixture, and soldered the ballast wires to it. It has a regular lightswitch just inside and above the door, to turn it on just like the not-quite-but-almost-as-ancient four-bulb fixture in the "barn shed" under the big mulberry tree south of it.
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plus a couple of the kitchen with the shoplights over the island / workspace, first with them off but just the regular kitchen lighting, and then with them on.
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You can see how dim the other lights appear to be with the shop lights on, which use four LED bulbs, 6500k, something over 2000 lumen each bulb (don't recall exactly).

I'm using these 2900 lumen 6500k fluorescents
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in the other fixtures like these cheapish shop lights
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such as this one over a workspace in the back room by the back door (this is one of the spaces that needs at least 3-4 times the amount of light it has right now)
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Anyway....still hoping for a super cheap way to use those cheap 65w CFLs.
 
Have you not seen the new 20-30-50-100w LED COB modules?
Just heatsink and apply 110V AC (220V available also)
AC modules, that I've tested, draw reasonably accurate wattage.
Have HSC (Heat Sink Compounded) and pop riveted multiple to old-heavy 4' fluorescent fixtures for shop and grow lights.
("full spectrum" grow lights available also - eerily make green plants appear black, no green-yellow to reflect)

UPDATE - 6000-6500k modules at great price


< $1.50 each

12V modules available also

Have HSC and pop riveted to old p3 heatsinks w/fan and hung as grow lights
30w 12V module uses 18w @ 12.3V ... designed for up to 14V+ vehicle use = 30w?

LED Full Spectrum grow info
 
LED COB modules need diffusion panels, or indirect, for living areas!
Modules are intensely bright! and leave ghost images in eyesight if not softened-diffused.

These have worked, limited travel, with light dimmers. 100% - 0% in 100% ~ 75% positions.
 
DrkAngel said:
Have you not seen the new 20-30-50-100w LED COB modules?
No, I had not--thank you. Assuming these are sufficient brightness, then they are much more cost effective than what I was looking at doing.

I checked out the link, but I didn't see a lumen rating, or a direct comparison to something else I know the brightness of. Do you happen to know what they are, or of a comparison?

I would just like to know how many of them it would take to provide the light I am after.

I would *guess* that a 50w unit (there aren't any 100w listed on that page), if 50w is the amount of power it *actually takes* to run one, would be about the same light as at least one of those CFLs, probably more, based on the power-to-lumen ratio of various LED bulbs I already have here.


I have some giant heatsinks, several pounds each, on some old network-equipment PSUs, so I could bolt or rivet several of these COBs to one for a high-up yard light on a pole to replce the the failing halide lamp, and make at least one more of them for another area of the yard. I could use others like that mounted under the eaves of teh house to light that area, too, if necessary.

I also have a number of old CPU heatsinks that could be used for single modules.

I wonder if bolting COBs directly to the main roof "beams" of the steel sheds would be sufficient heatsinking (especially in the summer)? It isn't as good a heatsink as the aluminum CPU stuff would be, but there is a lot more surface area.
 
Poking around that seller, I found these:
https://www.ebay.com/itm/LED-Flood-Spotlight-30W-50W-100W-110V220V-LED-Reflector-Spot-light-heatsink/252874367047?hash=item3ae07ca047:m:meKEtfC7LHcGulByoMLz9yw
that claim 2000 lumen and up; the wattage starts at 30w so if 30w is 2000 lumen, 150watt should be 10000 lumen?


Looks like there's quite a few options out there.
 
+255
Finding detailed data on fluorescent tubes is very hard, and surprisingly enough, internet search engines are of little help. In spite of the large majority of electronic components where their manufacturers specify in great details all the electrical characteristics, for fluorescent tubes, it's difficult to find any datasheet with more than the nominal power and the mechanical dimensions. It's therefore very hard to answer questions like: what is the striking voltage? What is the burning voltage of the lamp? How does the current looks like when the lamp is on? I had these questions in my mind for many years, until I decided to hook up a lamp to a high voltage oscilloscope probe and have a look by myself at what is going on.


id est:
 
Toorbough ULL-Zeveigh said:
http://www.giangrandi.ch/electronics/fluorescenttubes/fluorescenttubes.shtml

That's an interesting tech page about the fluorescents, thanks!


@DrkAngel: I went ahead and ordered a few of these
https://www.ebay.com/itm/LEDs-Floodlights-COB-Chip-20W-30W-50W-Input-Integrated-Smart-IC-Drive-110-220V/113735280713?hash=item1a7b26a849:m:migcEfWdgCGi3NoBUwYm7-A
in the brightest version for 110VAC, in 6500k, we'll see how they turn out in a month or so.

If they work out, I can use some for direct lighting of work / yard areas, and some for indirect lighting of the house interior. (for instance, there is about a foot or more between the tops of the kitchen cabinets and the cieling, so a light mounted above the cabinets pointed at the cieling would light the room without directly blinding anyone looking up. )

I also ordered one of these large 12v units to probably replace the failing halide lamp/ballast on the pole-mounted barn light. (if not, to build a new pole-mounted fixture, most likely).
https://www.ebay.com/itm/262986434095
I think I have a couple of 12v PSUs large enough to run them at full power; not sure if they're current-limiting in the right way so I may have to make a current limiter circuit for them (some type of pass-transistor, probably; wasteful of power and makes a lot of heat but it'll already have a big heatsink for the LED to mount on anyway).

Specifications
Power: 160W
Input Voltage: DC 12V-14V
current ; 1300ma
Luminous flux: 14000-16000LM
Light Color: Pure White(6000-6500K)
Size: L 220X W 112MM
Pretty sure they lost a zero on that current figure though: to get 160w power at 12v it'd ahve to be over 13A input.
 
Hopefully the way and places I'll use these won't need those covers; or silicone will seal them well enough, but ti's good to know they exist if I do need them. :)


Both of the LEDs I've got on order are definitely on their way; the larger brighter 12V panel has already cleared import customs and is on it's way from San Francisco. The smaller 110VAC units are still at the "export customs declaration completed" stage, after having departed the regional distribution center.


I'm still looking thru my "broken junk" for a capacitor I can replace in that ballast, to try out the original thread topic CFL with it, minus the built-in bypass cap in the ballast.

(I am in the slow process of consolidating my test equipment and spare parts into the back room for an electronics workstation area, and all the computer-related stuff into another part of that room for a computer-repair/build workstation area, and my hand tools in a third part of the back room just so I know where they all are, instead of scattered around different projects, as I have tended to leave all this stuff for the last several years since the housefire rebuild. Been working on this off and on for quite a while now, and it's getting to the point I can actually find things I need close to when I need them. :lol: :oops: I've also been finding new homes for stuff I will never fix or use, if it can't be used for spare parts for something I *am* using; this has turned out to be a fair bit of stuff, leaving room for things I *am* doing stuff with, and room for working on or with them, rather than feeling like I live in a storage facility. :oops: )
 
The large COB LED panel arrived; it works, using an old XBOX power supply (theoretically capable of 16A at 12V), but the voltage drops to a bit more than 11V when directly connected to the LED, and it's doesn't light the room nearly as bright as I would expect for roughly 14000 lumens; it's probably not enough current or enough voltage, or both. It also only gets fairly warm, not hot, though it's not heatsinked beyond the ~1/16" thick backing plate.

I'll have to hook up the big Sorenson (DCS 55-55) and adjust it until it reaches the peak current / voltage to see what it really lights up at, then see about making or modding something that will do that up on a pole.

The first and last pics are with a large resistor set in sereis with the +V line, which reduced voltage to just above 10v. It's bright, but not uncomfortably so.

The inbetween pics are bypassing that resistor set, which gives just over 11v. It's so bright I wouldn't try looking at it, and the camera's dirty lens is lit up so well the camera focused on *it* instead of the panel. :lol:

I don't know the current on either one; didn't instrument for it (the fluke's fuse is still blown, not yet gotten around to replacing that). I'll know what the current is when I setup the Sorenson.



The other LEDs are still on their way; last status was:
Monday, Nov 11, 2019 5:56 PM SOUTH SAN FRANCISCO , CA Departed warehouse
so based on the timing of the other one will take about a week more to get here.
 

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Any computer PS should supply a good 12V high Amps, I stocked up on Dell DA-2's for 12V 18A in a nice package, about $10 each in quantity.
LED panel might draw 160w at 14V but likely less than 60w at 11V. Voltage >> brightness is more exponential than linear!
Higher voltage permanently dims LEDs, so do not push past the rated 14V! Start at 12V and increase voltage to acceptable, increase voltage slightly as LEDs "fade with age", to maintain acceptable brightness?
"12V" LEDs are very voltage sensitive. Most rely on native voltage rather than any active regulation, 4s (3.0-3.5V) LEDs for "12-14V".
Voltage alone determines brightness and amp usage. High Amp draw drops voltage from supply, dimming LEDs.
LED "string lights" use 3s + resister to drop 12-14V voltage to 3.0-3.5V per LED

Recommend MeanWell S-150-12 @ ~13.5V for continuous 150w near 15000Lumens (16ga or higher wire @ 10A+)
Heatsinking will definitely become advisable as voltage is increased to 12V+, monitor closely!
Fluke fuse is 10A and not worth potential damage to replace with higher?

Recommend - Volt Amp Watt etc. meter <$10
 
DrkAngel said:
Heatsinking will definitely become advisable as voltage is increased to 12V+, monitor closely!
200w into power supply is 80% efficient = 160w 12V 40w heat.
160w LED is ~20% efficient = 32w light 128w heat.

110VAC COB typically use a bridge rectifier and small cap(?) to push ~158DC through ~48s LED.
COB without any cap might run with some 60Hz flicker, but haven't noticed any. Perhaps so brilliant my retina retains some latency? Will need to test with COB at distance, viewing in periphery?

Multiple 50w heatsinked into old exterior fixture recommended as easiest, most efficient method for "yard" or "shop" application.
Small single serving pie tins as reflectors?
On-Cor family size tins as 160w reflector?
 
edit: added pics

Misplaced the memory card so have to attach pics later, but I got it mounted to a heatsink (no fans). I used the existing threaded holes to do this test, and some old CPU thermal paste. (found out most of my old paste that isn't plain old titanium dioxide stuff had hardened into rubber, at best--I'm probably going to have to buy some new paste to do all the LEDs as they arrive). The panel is not perfectly flat to the heatsink on it's own, probably got sligntly deformed in shipping, since it was just sent in a puff-pack mailer, internally wrapped in a couple layers of very thin closed-cell foam. So I clamped it down as best as I could with the existing moutning holes and some hardware that was quickly findable.
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Testing with the big Sorenson determined that peak power point is around 170w input power per a Turnigy Watt Meter. Current about 12A, and voltage 13.6V.
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Over about an hour, heatsink temperature slowly climbs in still air in the utility room from original ambient of 75F to about 185F. LED panel temperature varies a fair bit over the surface area, from around 120F to almost 200F. So it'll need a fan on the heatsink in operation inside the pole-mounted fixture.
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As for brightness...it doesnt' seem bright enough. Can't find my light meter to quantify objectively, vs other lights I have, though.

Might take multiple panels to replace the yard light; I have two poles (the other is shorter; it was originally teh base pole for the one I'm using for the barn light fixture, but I didn't need it that tall), so I could make another one over a second area of the yard if necessary.

We'll have to see once it gets dark out there, and I can put the panel out the window to see what it lights up, on an extension cable (don't have one I can put the Sorenson's input on; I guess I could make an input plug for it that would use the welder's power cable, but the Sorenson is big and heavy, so I'd rather not move it around).

If it's about half the brightness I need, I can just use a second one with it (the heatsink will hold two, side by side, if mounted perpendicular to how I did this one.



I also checked out the XBOX PSU, and it's got a potentiometer on the daughter board with the control circuitry, but it doens't control the voltage; unloaded stays at 12.02v. Haven't gone searching for internet posts about what it does control. There's a spot for a second pot near it, but it's not installed, nor are a few other passive parts in the same area. So that might be a voltage trim pot, and is using just a divider bridge instead, perhaps. If I'm lucky, someone else has already fiddled with one of these to alter it's voltage; I only need to go up about a volt and a half, but that's more than 10% of it's present output, and it may not be capable of that much even if I can find a way to adjust it.
 

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Did one more test before laying down for the night; made an "extension cord" from some 14g speaker wire (all I had that was long enough in one run and not already in-use), just twisted and taped to the existing wire on some salvaged SB50s out of the connector box, to make an extension from the Sorenson's SB50 output to the SB50 input on the wattmeter.

Needed the wattmeter on the LED end of the extension so I could see the voltage drop at that end, and then compensate for it at the Sorenson's output. That turned out to be about three volts, which makes a significant difference in brightness, quite noticeable in how much of the yard it lights up.

So I strung the extension out the window and to the same spot as some LED floodlights I use to light the carport gate area, and put the heatsink/LED setup between those lights in the Y of the tree trunk they're mounted on.

The first pic is just the floodlights, and the second is the COB LED, in each of the picture pairs.
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A test with it just sitting on the ground, aimed diagonally into the rest of the yard, from near the house corner.
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Some pics in the kitchen; first with just the pair of shoplights, each with a pair of 1900lumen LED lights, for a total of around 8000 lumen shining directly down on the workstation / central cabinet. Then with both those and the LED COB light, which is sitting in the corner on top of the cabinets, near the cieling, shining outward diagonally across the kitchen. Then just the COB light.
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It doesn't look like a lot of difference, but the F-stop teh camera autoadjusted to is 4 in the middle pic, with both lights, with 1/60sec exposure. Just the shop lights is 2.7 & 1/60, and just the COB is 2.6 & 1/50. (some of that is probably because I didn't get exactly the same shot framing in each pic, but some of it is the difference in light output).

I was going to put some stuff across the two shop lights to put the COB between them shining down, but my random hand numbness led to me dropping it on the floor (first bouncing off the cabinet then the stepladder tehn my leg then the floor a few times), so now the COB's silicone coating (which includes the fluorescing material) is damaged in a few spots. :/ Still seems to work fine, thankfully.
 

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12V - price, power supply, heavy gauge wire, line drop ...
110VAC modules looks better in every way, except more intense points of light.
3 - 50W modules cost half as much as the 1 - 160W 12V module. Could put 6 in the same area, 300w 110VAC same price at 160W 12VDC, using mains voltage over light ga wire with minimal line drop!
 
Yeah, I wanted to try one out anyway. :)

Plus, being 12v it can be easily run off battery as a backup lighting source in case of power failure, though those are extremely rare here nowadays).

It's also usable as a portable light source (battery powered) that could be dimmed, or used to make a well-lit area, etc.

The set of 110VAC COB LEDs will be here within the week, so I can see how those work out.


I didn't find a conveniently-documented voltage-increase hack for the XBox360 PSU yet, but it'll still work just as it is, albeit at a lower brightness, if I don't run across the other large 12v PSUs I have somewhere around here.
 
The smaller COBs arrived today while I was at work; I'm too wiped out from work and the changing weather (all my bones ache) to do any significant testing, but I wired up one single and one set of four to just plug in and test general brightness.

They are very very bright, and seem like they should work out ok, though they get real hot real fast, absolutely definitely need heatsinks. :)

It's going to rain starting Tuesday (potentially earlier) so before I can spend time on these lights I have to move stuff back into the sheds that I'd taken out to sort stuff, and do some other stuff to ensure I can get teh trike thru the dirt-only section of yard from the gate to the back door once that area turns to mud with the rain. (typically I use large cardboard boxes from stuff my brother has shipped to him here, opening the boxes up flat and spreading them overlapped in a path from the gate to the back porch).
 
Careful, heat permanently degrades ≫ kills LEDs! (High voltage too)
Damage evident by reduced watt usage.

And yes, important to not look directly at brilliant LEDs!
Building a "Sun" with multiple 50w in heavy Stainless Steel globed fixture, still, don't stare at the Sun ...
(Still looking for small cheap 110VAC fans for heatsinks)
Update - 60mm 110-220VAC fans 10 @ $6 each

AW - might want to edit title with " ≫ LED projects "
 
Thanks, good idea--did that just now. ;)

I know heat's bad for LEDs (and most other electronics); I've got heatsinks to test stuff out with, just had to see what they'd do before heatsinking.

I tried out a couple different CPU heatsinks with the first COB, it's either going to need a fan or a much larger heatsink.

The first was just a plain old aluminum one with large ~1/8" "fingers". I clamped the COB to the heatsink, with a really thin bit of paste well-distributed between them. LED silicone surface temperature reached over 230F in a couple minutes, while heatsink temperature was only half that. The aluminum plate of the COB, and the other electronics on it, were only in the 170F range.

The second was a copper heatsink with very thin (paper thin) fins, and it kept the LED surface down to 200F, with the rest of it in the 150F range. The heatsink reached 140F range.

It's possible that bolting or riveting the COB to the heatsink, vs clamping it at a single spot, would make a difference, and perhaps better thermal paste would, as this stuff is probably more than a decade old, and is the plain old white stuff (though from CoolerMaster rather than some of the really generic stuff; at least it's still well-mixed, and not gooped up or dried out, etc).


A fan would make more difference, but ideally I'd like to run these without fans; those add noise, complexity, power use, failure points, etc.


As a note, these arrived in two continous plates of four, and one of two. I split the pair up to do these tests, but I also wired up one of the four-plates with them all in parallel, no heatsink, just to power on to see how bright they'd be for a few seconds.....pretty bright. ;) I'll redo that test after I mount them to that big heatsink presently holding the larger plate LED. Then i can compare the four of those with the one big panel in direct A/B testing outside at night.

But probably not till after the rains let up most likely a week from now, once they start on Tuesday.

Oh, and the last pic fo the LED lit up shining on the rest of them, is with the same lights in the kitchen on as in the other shots. It's just the brightness of this one is so great it drowns out the rest of the light shining on them. ;)
 

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Proper heatsinking is essential.

" LED lights are designed to function in temperatures of -25° to 140°F, making them suitable for most indoor and outdoor LED applications."

White LED Cob temp above 55ºC 131ºF reduces brightness and lifespan.

Owning a computer shop I have a large box of old heatsinks, being collected for aluminum scrap, but they still require fans for continuous operation. Exceptions are light fixtures.
I have several non-fanned builds:
1. 10" metal base glass globe. Base is about 10", the type for 2 x 60w bulbs. Pulled top and bottom insulation, cleaned, applied 2" copper foil tape under 20w COB, base metal is too thin so sandwiched between COB and 1/8" x 2" x 10" aluminum stock and pop riveted together. Used 3200K as direct replacement for warm room light at 18w LED @ 130ºF replacing 120w incandescent @ 400ºF.
2. Old, heavy 4' fluorescent with 3 x 30w 6500K spaced at 8" 24" 40" and pop riveted (w/heatsink compound) to the heavy steel reflector, type with downward wings.
3. Dual 250w Halogen floods, on stand, innards removed, smoothed, lined with coated aluminum foil tape and 30w 6500K COBS attached to oem heatsink type rear panel
4. Still working on heatsinking to outer casing of old Sodium Iodine commercial fixtures. But think I will resort to 110VAC fans with computer heatsinks, convecting hot air to the cast aluminum shell and heavy glass lens? Should be able to run 2 or 4 x 50w COBs in the different sizes I acquired.

Been on the lookout for scrap or cheap copper sheeting and soft copper pipe to better distribute heat .
 
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