DiY LEDs - How to Power Them

SupraSPL said:

PAR meters, even apogee, unfortunately cannot see red, deep reds and blue as well as it can see greens/yellows etc. So the measurements are not absolute figures, but they can be used for relative comparisons. However, at 24" you would need a good reflector, which would very significantly boost the light, maybe 30%. Even at 12" a short reflector would be a nice boost.

136V is a strange reading for sure, 34V each, what method are you using to dim it? Do you have confidence in the accuracy of the voltmeter? And were you able to check the current of the LED string and/or power draw at the wall?

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SupraSPL said:

Very cool setup, but to give fair warning, those heatsinks are going to get super smokin hot. Each will be trying to get rid of 21.5W of heat and since the fins are so close they need more than just convection they need "pressure" between the fins. In my testing I measured CXA3070 AB @ 1.05A on CPU cooler with no fan - heatsink temps reached 55C and rising so I stopped the test. Temp droop was 12.7% and rising.

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SupraSPL said:

Gotcha, in that case no worries We have a reflectors thread going but it is mostly about DIY reflectors. You can make them out of cardboard, plastic or metal and paint them with Rustoleum White heat paint and get excellent increase in intensity. I believe prefab options are discussed there also.

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Observe & Report said:

high voltage + ungrounded metal frame = bad idea

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stock said:

Thank you !!!
My goal to build led compatible to 1k hps ,below $1k soon is possible ( i know ,you guys put lot of effort to do so ,and i am just follow you footsteps,i am not even sure how outcome will be ) ,because i need bunch of them ,to cover around 2500 sf total .I don't mind to buy at600 ,but price is no go for me Area 51 was my other thought ,but same thing ,i need 4 of area 51 to match 1 at600 ,price will be almost the same

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SupraSPL said:

https://www.rollitup.org/t/diy-cob-reflectors.854312/

In a nutshell, the best performing reflector I came up with so far is 2 liter soda bottle. Cone shape works very well also. The best paint performance by far was 2 layers of Rustoleum White Heat paint 7751
View attachment 3332824

SDS experimented with stainless bowls and had some success, although he was not happy with shape overall.

The glass lens that I tested performed surprisingly well but it shifted the color temp toward warmer white so I am not sure how that affected the cheapo luxmeter readings. Also it got very very hot while the reflectors did not.

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Greengenes707 said:

PAR and cobs had been throwing me for a loop ever since I started dabbling with them. It is not hte same as we usually know it...at least the distance drm the source part. Usually that would translate into penetration. But I am getting just as good if not better penetration from my drone as my at600's. And it is ~12" away giving 600-900µmol...the at600 are ~24" and putting ou 1200µmols.

Apache uses lenses which collimate and bring almost all the light to the canopy...making the PPF and PPFD closer to matching. But if you take the lenses off...there is no difference in intensity and the cxa's even have a slight advantage...which since they should give off a higher PPF...they should have a slight advantage if all else is equal...like lenses vs lenses, or no lenses vs no lenses.

At this point I have come down to that distance from the source is not as important as I once thought. If I supply the canopy with the right intensity, it translates into the normal growth and penetration I usually associate with hps and at600 distance...even though it is closer to the canopy. A very strange phenomenon that I can't quite explain right now...but am trying and more testing will help clarify. The ability to spread PPFD by design is what I think throws the big wrench in it. When clustered like a bulb of conventional LEDS, they react/perform similar...with higher par numbers at a distance...but sacrificing the spread.

As of now I am going on that PPF is the most important, and actually very telling if you can use some though to see how that PPF will be distributed over the canopy and turned into PPFD(PAR readings).

I am also experimenting with pre made reflectors. But the minimum orders kind of kill the ability to try multiple different one. But they help tremendously with the COBs and will get them even closer to the mid blowing PAR numbers the at600 and gavitas put out.


SO my suggestion after all that is to find the place where you get the best coverage and peak µmols between 500µmols and 900µmols...700µmols is plenty and will make grenade sized nugs no problem.

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DonPetro said:

Anyone use this type of hook up for their fans?
View attachment 3333735
View attachment 3333734

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Abiqua said:

Yes....i use these for my non hacked Power Supplies, lol, they work good....

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CatSpeaker said:

Good morning,
Having read this thread and others in the forums, I have a design question.
I'm building a couple lights using 3070s and 3590s.
If I understand the principles correctly the HLG-185-C1050 fits with what I want to do.
I can run 4 3070s or pair of 3590s for each driver. Vf for the 3070s is 38.5 and the 3590s is 77.
Am I reading this right or am I out in the weeds?

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CatSpeaker said:

Good morning,
Having read this thread and others in the forums, I have a design question.
I'm building a couple lights using 3070s and 3590s.
If I understand the principles correctly the HLG-185-C1050 fits with what I want to do.
I can run 4 3070s or pair of 3590s for each driver. Vf for the 3070s is 38.5 and the 3590s is 77.
Am I reading this right or am I out in the weeds?

Click to expand...