Heatsinks for DIY LED lamps

SupraSPL

Well-Known Member
Ya it has crossed my mind that maybe it was something else that caused it. Maybe I hooked up the COB to the HLG-180H-C1050B while the switch was on and it got damaged without my noticing. Also, the actual Tc may have been as high as 85C, but still should have been OK with that heat at 1050mA.
 

bicit

Well-Known Member
Uh oh I fried an egg in the 1.05A passive test. I let it get much hotter than I normally would (hottest part of the heatsink ~60C+) and now the Vf has risen (permanently) from 37.3 to 41 at 1.45A. Along with the power consumption increase, I am also noticing a decrease in output of about 20-25%. Maybe this is why:
View attachment 3311214

The max Tc for 1.05A is 125C and I was nowhere near that, so I am surprised that it was damaged. One way to find out how much is too much, a sacrifice for science :joint:
The vero's can tolerate some abuse then. A fan didn't get plugged in an a vero 18 ran for several hours driven at 1400ma with seemingly no ill effects till the mistake was discovered and corrected. I wonder if that CXA was a lemon?
 

FrozenChozen

Well-Known Member
Uh oh I fried an egg in the 1.05A passive test. I let it get much hotter than I normally would (hottest part of the heatsink ~60C+) and now the Vf has risen (permanently) from 37.3 to 41 at 1.45A. Along with the power consumption increase, I am also noticing a decrease in output of about 20-25%. Maybe this is why:
View attachment 3311214

The max Tc for 1.05A is 125C and I was nowhere near that, so I am surprised that it was damaged. One way to find out how much is too much, a sacrifice for science :joint:
I fried a feit today as well. I was experimenting with lenses... no more fucking around, these things aren't exactly cheap, and its a pain in the ass scraping a cooked cob off that's been attached with thermal adhesive....
 

Positivity

Well-Known Member
I ran a few tests on coolers..put some stuff up in my thread. I can repost it here if you want.

The sunon downlight cooler is really good. It needs a better fan than what it ships with but otherwise works well.

The dynatron r24 can do some amazing cooling but its way too loud. Don't even bother trying that one.
 

SupraSPL

Well-Known Member
Awesome info POS, please feel free to post anything you want here as well. That dynatron looks pretty sweet. I have an OCZ vanquisher to test that is in the same category, but I like the direct contact heat pipes on the Dynatron
 

PurpleBuz

Well-Known Member

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SupraSPL

Well-Known Member
Seems like they have kind of the same problem as my heatsinks. If the fins were running the other way, I imagine the fan power would be much more efficiently used? The big one is $49, smaller is $34 at Digikey. Looks like the larger one uses 4W for 3 synjets, running at 12V.
 
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Abiqua

Well-Known Member
@SupraSPL

wondering if you [OR ANYONE] could give a quick opinion on these..Thermaltake Volcano 7+ coolers. They even have a 3 way fan switch [but all resistors] included.

http://www.overclockers.com/thermaltake-volcano-7/

Running a max of 1.4-5a's...... at this point so that would be max for the a AB3070, I plan for these......

The reason for asking for an opinion, is the copper construction. That's my only concern really. The small fan at higher RPM is a slight concern, but maybe it is more essential for narrow, somewhat deep fins. Although thin walled in this case, another slight concern.

I can score them for $4 apiece though......preciate it again :peace:
 

SupraSPL

Well-Known Member
One pound of copper with a direct thermal path and decent surface area, it should perform awesomely. For a CXA3070 AB at 1.4A though, there is not much room for improvement over the Apline11 (~2% temp droop). You could bypass the 3 speed switch and just power the fan directly with a 5V or 6V. Should be quiet and efficient that way.

$4 ea, tough to beat that deal! Is there a decent supply of them?
 

Abiqua

Well-Known Member
One pound of copper with a direct thermal path and decent surface area, it should perform awesomely. For a CXA3070 AB at 1.4A though, there is not much room for improvement over the Apline11 (~2% temp droop). You could bypass the 3 speed switch and just power the fan directly with a 5V or 6V. Should be quiet and efficient that way.

$4 ea, tough to beat that deal! Is there a decent supply of them?
Oh snap, so what is a general predication on higher amperage, could I get to 2.1A at any point?[i guess I thought they seemed a little small with the 70mm fan....my bad]

Craigslist find, might get 3 altogether.
:) I was just sitting down to buy some Arctic's too! But jumped online and found these. Might happen might not. The switches I probably won't use, but might try. I have handfuls of cellphone power supplies.... [who doesn't] too.....

But have been thinking and started investigating tonight, about building a DIY variable control with a LM1084IT-ADJ or something similar. I have the schematics, easy to build with a pot, cap and two resistors I believe.....

Need to review again about measuring efficiency. What was the Fluke Model you recommended? Thinking about possibly dipping my toe in that pool......:peace:
 

SupraSPL

Well-Known Member
Ya they are a bit on the smaller side, but with thick copper pad and skived fins direct thermal path and lots of surface area, they might be perfect for our purposes.

I like the Rosewill Z200 you linked too, $11 ea on Amazon
http://www.amazon.com/Rosewill-RCX-Z200-92mm-Ball-Cooler/dp/B002CT19IY

The Z100 still has a large copper base, maybe less surface area, $10
http://www.newegg.com/Product/Product.aspx?Item=N82E16835200017

I use a pair of multimeters to monitor current and voltage at the same time. Saves time and can get you a more accurate measurement by removing temperature change variable. Also reduces the possibility of me blowing stuff up by plugging the leads into the wrong holes when switching wires or selecting the incorrect setting for the measurement. If you try to check voltage while in ammeter mode, bad things happen. Blowing multimeter fuses can be a nuisance. Anyway I use a Fluke 115 and an Amprobe AM-520, both accurate and affordable multimeters for electronics. Either meter can do either job. AM510 a few bucks cheaper also a great meter.

I modified the wires to make it easy to bug into circuits. Modifying probe wires can be a tricky business, they need to be rock solid connections so that they do not introduce any voltage drop. The ammeter itself will introduce a slight voltage drop to the circuit.

DSC07777a.jpg
 
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