DiY LED - Cree CXA3070

bizfactory

bizfactory

Well-Known Member
churchhaze said:
I really like these angle profile rail designs, but I'd imagine the rail blocking the exhausts has a serious effect on cooling. I wonder how big of an effect it makes in practice, and if it's possible to fix with slots or something.

Nice design!
Click to expand...
Yeah the reason we went this orientation was because of the base of the coolers. You can see the raised portion of the heat sink with a straight edge that made lining everything up square really simple. Didn't think about the airflow right away but once we did and hooked up the fans, no problem. It does disturb the airflow but I have absolutely no doubt it will be enough to cool these at 50w.

Is 22 gauge solid core wire good for running to the LEDs from the driver? Says rated up to 4 amps 300 volts so I don't see why not...bad idea?
 
bizfactory

bizfactory

Well-Known Member
churchhaze said:
22 gauge should be fine as long as it's not too long a length. I usually use 20 gauge for lower currents and 18 for higher, and longer lengths.

I doubt it will be an issue really.
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Thanks. The entire thing is 24x11 so not much distance to cover. Nervous about soldering to the LEDs. Almost there!
 
Doer

Doer

Well-Known Member
bizfactory said:
Yeah the reason we went this orientation was because of the base of the coolers. You can see the raised portion of the heat sink with a straight edge that made lining everything up square really simple. Didn't think about the airflow right away but once we did and hooked up the fans, no problem. It does disturb the airflow but I have absolutely no doubt it will be enough to cool these at 50w.

Is 22 gauge solid core wire good for running to the LEDs from the driver? Says rated up to 4 amps 300 volts so I don't see why not...bad idea?
Click to expand...
You are most correct. When down firing into a heat sink the air is "blocked" within an inch or so, by the fin bottoms. Nothing much matters after that.

Big mixing is more important here I think.

And get used it. We can't put anything up here, for a second until someone tells us to change it.

22 gauge will work just fine.
 
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Doer

Doer

Well-Known Member
bizfactory said:
Thanks. The entire thing is 24x11 so not much distance to cover. Nervous about soldering to the LEDs. Almost there!
Click to expand...
Read up on soldering to pads. That's what I do every time. I just soldered onto a pad on a $500 drone GPS unit. That was a nail bitter. :)

You know, my entire solder world changed when I decided to spend a $100 and get away from cheap Wellers.

I got this puppy. What a difference in temperature control!!
http://www.adafruit.com/products/1204
 
alesh

alesh

Well-Known Member
It's difficult for my ego to admit it, but @Doer is right on this one. Good soldering equipment makes the difference. Combine it with some patience and you can't blow it. Also if you're nervous you might do some training on some old/broken electronics (old power supplies, ...).
 
Greengenes707

Greengenes707

Well-Known Member
bizfactory said:
Yeah the reason we went this orientation was because of the base of the coolers. You can see the raised portion of the heat sink with a straight edge that made lining everything up square really simple. Didn't think about the airflow right away but once we did and hooked up the fans, no problem. It does disturb the airflow but I have absolutely no doubt it will be enough to cool these at 50w.

Is 22 gauge solid core wire good for running to the LEDs from the driver? Says rated up to 4 amps 300 volts so I don't see why not...bad idea?
Click to expand...
I do it for the same reason...heatsinks fit and don't move when oriented that way. I originally used the same "L" frames. Like you said...the flow is fine...just blows more up and out than sideways out, but all good. I did cut out notches where the heatsinks are on a bar, but no temp difference measurable. But recently I started using the lower profile L's. They have shorter side that doesn't block the flow hardly at all. And is still bigger on the bottom for mounting.

For ideal connectors I have been using 18g...more than enough
But since going to bjb connectors they need a smaller guage so I have been using 20.
 
Doer

Doer

Well-Known Member
Come on. We are all friends I thought and still do.

I am a DIY maniac. I build constantly, on several projects And I like you guys. You helped me a lot. My ego has no problem with that. :)

I was the worst solderer and now I do OK. A lof of stuff is all about the equipment.

Just not golf, alas. For most equipment is meaningless. When I learned that, I learned how to have fun at failing. That is the game.
 
Doer

Doer

Well-Known Member
alesh said:
It's difficult for my ego to admit it, but @Doer is right on this one. Good soldering equipment makes the difference. Combine it with some patience and you can't blow it. Also if you're nervous you might do some training on some old/broken electronics (old power supplies, ...).
Click to expand...
Perfect practice makes proper performance. Oh and for my old eyes a lighted magnifier makes it much easier to get those perfect joins.
 
alesh

alesh

Well-Known Member
Doer said:
Perfect practice makes proper performance. Oh and for my old eyes a lighted magnifier makes it much easier to get those perfect joins.
Click to expand...
While I don't need a magnifier (yet), good lamp helps too. "Third hand" tool is also pretty useful.
 
Doer

Doer

Well-Known Member
I use a pair of those 3 hands. Great for solder splicing. Holds both ends together a lot easier than trying to work both clamps on one.
 
K

Kuifje76

Well-Known Member
SupraSPL

SupraSPL

Well-Known Member
Thats a good question. I am testing that in a few days to find out for sure, wired 4 drivers with a 25K pot. I just connected all the whites together and put that on pin #1, tied all the blues together and put them on pin #2 middle pin. I am dwhat happens if I cut the power to one of the four drivers, would my 25K pot no longer be the correct value? If so maybe I should use a 50K so I will get the full dimming range either way.

Dimmer 2.JPG

-the pot style above is a bit less than a single turn. If you want something with more precision you can get a high turn pot
-you can choose between linear and log, I use linear
-you can choose from different shaft lengths

http://www.ebay.com/itm/6x-B50K-50K-OHM-Linear-Taper-Rotary-Potentiometers-POT-w-control-knob-USA-/251875901679?pt=LH_DefaultDomain_0&hash=item3aa4f940ef
 
Cali weed

Cali weed

Well-Known Member
I'm placing a order for my driver and cob. I found a top bin cxa3070 3000k (ab) for 64$... that's 14$ more than the mid level bin (z4). Is it worth it? What is the difference between the low, mid and top bins? Z2 Z4 AB? Also I'm planning to use a meanwell lpc60 1040. Is that better than a chinese 1500? I know meanwells 1500 isn't power corrected and is less efficient. I don't know exactly what that means yet lol but I know it's no Bueno! Just not sure if a 1040 is too weak. The way I understand it is the higher the milliamps the brighter but also hotter which means they burnout faster and aren't as efficient. How am I doing so far?

PS I'm using an artic 11 pc cooler for this single cob light
 
SupraSPL

SupraSPL

Well-Known Member
The LPC-60-1050 would work. They are $17.50, non power factor corrected and 87% efficiency.

Other competitors:
If you do not mind open frame, the Mean Well PLP-60-48 is $16.20, dimmable, 1.3A, 89% efficient, power factor corrected.

If you do not mind open frame, the Mean Well PLP-45-48 is $15.30, dimmable, .95A, 89% efficient, power factor corrected.

If you dont mind waiting for them to get here from China, the 50W generic is about 89% efficient and puts out 1.45A and is power factor corrected.

You can get 1.25A drivers from Cali that ship quick, $13, 89% efficient, not power factor corrected.

Fot $11, the open frame 1.1A, 91% efficient Fasttech "50W" drivers
For $11, the open frame .88A, 90% efficient Fasttech "30W" drivers
 
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