cxa3070s@350mA orientation

Fiveleafsleft said:

Hi Scotch! Found this thread just now, and realize that we are thinking alike. Only that you seem more ahead of things and went for the deluxe option. I couldn't find any good binnings of 3070 and finally went with recently high-binned 4000k 2530's instead. Just couldn't justify the higher price for the 3070, since my electricity actually is for free. BUT Always liked optimizing, so had to find a middle way..

My space measures 45x96 cm about 1,5x3 f.( 0,43 m2) So will place my cobs in 2 rows of 4, on 8 smaller heatsinks. Heat sinks will be built in to 100mm vent tubes connected to the outlet. Stole this idea from sammyz2646 at this other forum, where i also have a pretty confused thread. Inspiration to drive cobs on low current, came from RIU, and some of its highly educated members, i think you know who you are. Thank you!

Will follow your thread closely, and i'm extra curious about what drivers you finally choose. I have only ordered cobs, and heat sinks, So I'm still in the process of choosing drivers and supplemental leds, to tweak the spectrum a bit.

Hope you don't mind me sharing this in your thread.

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Great minds my friend Five! FREE electricity is sweet electricity, id take that any day of the week and my bill is nothing to write home about! Feel free to post any questions you have here, this wasnt supposed to be where everything took off but i try to cut down on as much "space" on the inteweb as I can so I made it home! The drivers I've decided on, or supra helped find for me, are the Meanwell HLG-185-C700A's, super sweet drivers (94% efficient and when dimmed down they should go under 92% with the lower Voltage capacity) I really wanted to have the dimming feature so im glad he pointed me in teh right direction, thanks supe! Again, feel free to post what you need and take care!

big update, i was light a sissy school girl when I saw where the packages were from. got some hardware!! Guess I better get my A game on with how fast everthing is getting here, need to get my measurements on making everything symmetrical, get some finer sand paper and get this puppy goin!

i said something about it in another thread but when I dm the leds ill be adjusting the watts to each respectively, heres a little rundown for those who are curious: (if my math is right, gauging the voltage charts on the PDFs can be hit and miss)

@350mA:

3070s-94.64w (85.7%)
XM-L2s- 7.7w (6.97%)
EX6s- 8.09ww (7.33%)
Total: 110.43w

@500mA:

3070s- 137.2w (85.3%)
XM-L2s- 11.2w (7%)
EX6s- 12.38w (7.7%)
Total: 160.78w

@700mA:

3070s- 197.68w (85.3%)
XM-L2s- 15.96w (6.89%)
EX6s- 18.1w (7.81%)
Total: 231.74w

okay, picutres next VVV

Oh shit son. This is awesome. Can't wait to see it going.

Scotch089 said:

View attachment 3189001 View attachment 3189002 View attachment 3189003

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Someone got some abs..

This gonna be good

Hi again scotch, and thanks for your being so welcoming! Looked at those drivers to, but it's quite an investment. Probably an investment that's gonna last a wile, but still.. I love that you're not compromising about efficiency or quality! Nice ti see that the different leds you are using dimms so uniformly!

Scotch089 said:

Here's a rough estimate of the SDS using the link guod shared some time ago, it only has xte WWs so plugged 200w worth in for the cxas and only the original xmls

View attachment 3185126

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This looks pretty damn sweet! (is this the spectrum you will go with?) - especially since you are gonna pull a whoooping 185-190 l/w from your cxa's!!! My 2530's vill hopefully give around 150-160 l/w. I've been toying with the software at MBL to estimate spectras, But this software looks like it has more features? Can someone share the link again?

A nice "side effect" with adding reds, to my 75 CRI cob is that the CRI goes up to above 90. with a bit of royal blue it goes down to 87-88. Guess this might apply to your lights as well..

Good luck with everything!

Scotch, Those drivers really look nice, seems as you have good advisors! Looked at their spec, and now understand that you only need two of them to power your hole setup! That means that these super-efficient drivers all of a sudden are pretty cheap.

Do you think that you will need up to 700 mA in your grow area? (probably already answered in thread, but i had some problems following that discussion..) guess it makes sense to oversize a bit anyways - if you ever ever wanna get a bigger cabinet. I'm thinking about buying the 500 mA driver instead, since my cabinet is slightly smaller than yours, and having the possibility to dim down to 250mA when plants are really small..

Does anyone know if it's possible to dim cxa2530 to 250mA? Crees datasheets starts at 300 mA...

Talking about dimming, wouldn't it be better for you to have one knob for each driver? If you run different strains with different need for light, or ever would like to have a perpetual grow and place younger plants in one side of your space.. Just a thought..

Fiveleafsleft said:

Hi again scotch, and thanks for your being so welcoming! Looked at those drivers to, but it's quite an investment. Probably an investment that's gonna last a wile, but still.. I love that you're not compromising about efficiency or quality! Nice ti see that the different leds you are using dimms so uniformly!



This looks pretty damn sweet! (is this the spectrum you will go with?) - especially since you are gonna pull a whoooping 185-190 l/w from your cxa's!!! My 2530's vill hopefully give around 150-160 l/w. I've been toying with the software at MBL to estimate spectras, But this software looks like it has more features? Can someone share the link again?

A nice "side effect" with adding reds, to my 75 CRI cob is that the CRI goes up to above 90. with a bit of royal blue it goes down to 87-88. Guess this might apply to your lights as well..

Good luck with everything!

Click to expand...

Yup that's a ROUGH estimate of the spectrum, probably a little more 660, I said it wrong earlier- there will be x11 luxeon deep reds, but the program/link I used only has cree xte warm whites and no cxas so I used those for my SDS, just to get an idea, and it only had the original xmls. And no bins, so again, a rough estimate. From what I understand CRI is speaking to how even the distribution is in the spectrum, which I am sure is important an plays a role- but coming from a old school R/B mindset when I does got into LEDs, I am still a seriously strong believer in saturating the chloro A and B peaks as best we can and put CRI to the side for the most part. (Exception for heavy blue, can be good and bad- Erhum*- the 2011 GrowLEDHydro Spectra panels... I owned some and they gave me trouble with how much blue they emitted.)

Fiveleafsleft said:

Scotch, Those drivers really look nice, seems as you have good advisors! Looked at their spec, and now understand that you only need two of them to power your hole setup! That means that these super-efficient drivers all of a sudden are pretty cheap.

Do you think that you will need up to 700 mA in your grow area? (probably already answered in thread, but i had some problems following that discussion..) guess it makes sense to oversize a bit anyways - if you ever ever wanna get a bigger cabinet. I'm thinking about buying the 500 mA driver instead, since my cabinet is slightly smaller than yours, and having the possibility to dim down to 250mA when plants are really small..

Does anyone know if it's possible to dim cxa2530 to 250mA? Crees datasheets starts at 300 mA...

Talking about dimming, wouldn't it be better for you to have one knob for each driver? If you run different strains with different need for light, or ever would like to have a perpetual grow and place younger plants in one side of your space.. Just a thought..

Click to expand...

Yup there are see real gurus in this forum that have helped beyond belief, without them I don't think any of us would have the balls/trust to dabble in the DIY world. Again, thanks goes out to all of them for their hard work and great education! I do think driving at 700 will be enough, I hope lol, it's kind of a trade off, buy less emitters and drive them heavier (less upfront cost), or buy more and drive less (more expensive but more eff) to get the same amount of power. I do think spreading the wattage will help out a bit- I'm not sure what the smaller current will so to pentetration but I'm a scrogger myself so I am not to as concerned about penetration as I am even distribution over the area. Good point about separate dimmers, never thought about different strains/age, THIS is why the forum is so great. 100 perspectives consolidated. Rocks.

Speaking to wen distribution I changed up my cree's layout and FINALLY got the measurements dialed in they I think I am going to stick with. I THINK. Probably post a pic later. Take care everyone!

Scotch089 said:

Yup that's a ROUGH estimate of the spectrum, probably a little more 660, I said it wrong earlier- there will be x11 luxeon deep reds, but the program/link I used only has cree xte warm whites and no cxas so I used those for my SDS, just to get an idea, and it only had the original xmls. And no bins, so again, a rough estimate. From what I understand CRI is speaking to how even the distribution is in the spectrum, which I am sure is important an plays a role- but coming from a old school R/B mindset when I does got into LEDs, I am still a seriously strong believer in saturating the chloro A and B peaks as best we can and put CRI to the side for the most part. (Exception for heavy blue, can be good and bad- Erhum*- the 2011 GrowLEDHydro Spectra panels... I owned some and they gave me trouble with how much blue they emitted.)

Click to expand...

Hi, I agree with your thought on spectrum. Using high efficient cobs, and saturating the most photosynthetic wavelengths, probably is the way to go. Just found it to be a bonus that doing this, to the contrary of my beliefs, actually upped the CRI. (could be that i haven't really saturated the peaks) Beneficial for my plants, but also nicer for me, when i'm looking at them. There will be a slight rainbow effect in the edges, but that only makes it feel like if the plants were throwing a partying in there!

If you wanna get a rough idea of the spectrum you get you cab use the program MBL offers http://www.bmlcustom.com/custom-led-strip/ thats where my avatar is coming from. But you are probably familiar with it already? I found that the ratio gets about right, since most of my leds are twice as efficient as the leds they use.

How much blue gave you trouble? I'm aiming for 18% in early flower and 10-12 in late flower. To much?

Scotch089 said:

Yup there are see real gurus in this forum that have helped beyond belief, without them I don't think any of us would have the balls/trust to dabble in the DIY world. Again, thanks goes out to all of them for their hard work and great education! I do think driving at 700 will be enough, I hope lol, it's kind of a trade off, buy less emitters and drive them heavier (less upfront cost), or buy more and drive less (more expensive but more eff) to get the same amount of power. I do think spreading the wattage will help out a bit- I'm not sure what the smaller current will so to pentetration but I'm a scrogger myself so I am not to as concerned about penetration as I am even distribution over the area. Good point about separate dimmers, never thought about different strains/age, THIS is why the forum is so great. 100 perspectives consolidated. Rocks.

Speaking to wen distribution I changed up my cree's layout and FINALLY got the measurements dialed in they I think I am going to stick with. I THINK. Probably post a pic later. Take care everyone!

Click to expand...

Yes, thank's the masterminds that are helping the rest of us out! And thank's to you for sharing your work! Will probably go for the 700mA as well. I'm a bit afraid of working with high voltage so might use these drivers instead: http://www.futureelectronics.com/en/Search.aspx?dsNav=Ntk:PartNumberSearch|EUC/-144Q070DT|1|,Ny:True,Nea:True

More expensive and slightly less efficient, but very convinient with the four lower-volt-channels. But another advantage with your drivers is that you could keep using them, if you for some reason decide to upgrade to cxa3590 or other high voltage cobs.

If anyone has any thoughts about the drivers i linked, please let me know! (ment to drive 4 x 40-42V of cxa2532 and supplemental 3 watter each)

Have you run the numbers on a 0.7A setup? It depends a lot on how much you're paying for drivers, but when I run the numbers 1.4A and1.0A total expenditure (capital + electricity) is pretty much always cheaper than 0.7A until 5-10 years out. Not worth it due to Haitz.

A lot goes into choosing your drive current.

It depends on how much you are paying / kWh and there could be savings from decreased ventilation and air conditioning. You can take into consideration higher energy costs in the US as the dollar loses it status. In my case electricity is relatively cheap $0.13/kWh, but thanks to the high efficiency I have not needed to turn the AC on yet.

Another thing that affects that calculation, the higher the efficiency, the less heatsink and drivers needed to do the same job. That can help offset some of the cost of buying more emitters.

Mounted, greased, and set in stone. Still waiting on my xml2's, and just measured the locations for the 140mm Prolimatech fans, 1.25" in and apart from each other on the heatsink, puts them over the COBs almost perfect.

How much Pk3 grease are the rest of ou applying to the 3070s? I apply one dot to the stars (ex6s) and have a little come out the sides, I applied 4 dots on the corners of the COBs and a ring in the center and none came out the side- I think it will be okay, I know we don't want excess, but I also don't want too little and burn up my emitters ($$$)

I put about a pea size in the middle and spread it with the included spatula...as thin as I could get it without seeing the ceramic base
Putting it in the holder kinda messed up the pk3...so I had to resmooth it once set in the holder


Nice layout. I'd really like to see how those luxeons work with the cxas

Positivity said:

I put about a pea size in the middle and spread it with the included spatula...as thin as I could get it without seeing the ceramic base
Putting it in the holder kinda messed up the pk3...so I had to resmooth it once set in the holder


Nice layout. I'd really like to see how those luxeons work with the cxas

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Nice, I also put a very small dab in the center of the ceramic base and spread with the spatula included with the 5gram PK3 syringe I bought. I put the COB in the holder first though so I just spread the paste as thin as possible and then flipped the COB/holder over and screwed the holder to the heat sink.

On my first modules I did the thermal paste and kapton tape method like Supra does. I put a small bead in the middle and pressed down to spread the paste out. Im positive I got the TIM thinner this time with the spatula method. I used a very small amount and it wasn't seeming like it was going to be enough but I kept working it to spread it out rather than adding a hair more paste I wanted to try to spread what was on there to cover the whole surface very thin and see if there was enough paste on there to spread a full layer and it was just enough to not see the ceramic base.

Im a fan of the spatula method now for the COBs.

I love the setup! I put a small dab on each corner and a bigger dab in the middle. Then press hard on the four corners and hold it for 10-15 seconds. This will allow the PK3 to slowly spread thinner and thinner and most of it will come out the sides.

Not sure how much work it would be but, if it were me I would reset it to make sure the base fully covered with no air bubbles. Because the PK3 has such a high thermal conductivity, the TIM thickness will not come into play as much as full coverage of the plate (judging by Crees graphs). It won't burn up your emitters, but it can cost in efficiency and lumen maintenance.

On the other hand you are planning on running these relatively soft so it would not affect you as much, but for those running harder the thermal interface becomes even more important.

Observe & Report said:

Have you run the numbers on a 0.7A setup? It depends a lot on how much you're paying for drivers, but when I run the numbers 1.4A and1.0A total expenditure (capital + electricity) is pretty much always cheaper than 0.7A until 5-10 years out. Not worth it due to Haitz.

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Nope haven't run the numbers. I know that what you and supra are mentioning makes perfect sense.. But.. My electricity is for free.. Just like the idea of efficiency. LOL! Think this is something I have in common with TS.

Will also pay attention to what's said about pk3 application!

Thanks for all the insight you lucky ducks- I didnt get a spatula with myy pk3, I ordered the tiny tubes.. I did take a few off and scope out what the spread was like, applied a little more and lightly used a razorblade to thin it across. But as I went along, they were all looking pretty well covered, so I stopped. (I've already soldered some of the wires on the luxeons and COBs so it was making it a PITA) Hopefully things will be alright.

Question for the folk out there- after digging for answers it sounds likke pots and rheostats are just about the same thing just one more eff than the other at dissipating heat, im trying to figure out what I can dim my 4 prolimatech 140mm fans with, can I use the 100ohm pots I bought for the drivers? (specs for fans: 12V, .2A, so 2.4w and 60ohms..) If I cant use those can someone point me in the right direction, I cant seem to find 10w rheostats. (>25w, found a 3w'r but only 10ohm resistance and not enough capacity)

I think the drivers, pots, and xml2s are going to be the last things here. Waiting on one driver to arrive at the distributor and the rest is in china town. WOoooooo. Gives me time to cut and rivot the case though.

Thank you for all the adhesive insight, I did get my ideal holders set in place, and only snapped TWO 4-40 taps off in the heatsink.... ha... good god.

That looks so good man. Love the layout. Plus the efficiency you'll have. Just killer.

The center star looks like it could be close to the cob wires. But if you had to move it, sounds like you have it down now.

Thanks brother, hope life is treatin you right! Its been a busy time over here, acttually jsut dropped THE question on the ol' lady yesterday. She said no... just kidding. She was stoked. That on top of the new panel, little man growin up to be so stinkin smart- im on top of the world. Except the whole, yesterday and today being my only days off this entire month. Good money though..

The wires are super close, I was worried about it and it's only going to get worse when the xml2s get here,, but I should be able to angle everything around alright. After all the soldering and tapping I think im through the rough parts, as soon as I square this fan thing away everythinng else is just putting the parts together and closing the case If only... Hope youre doing well brother! Your setup really made me start analyzing how well these things spread, been wanting to take readings from a single COB to see what the falloff is like then we can really dial in the distance between emitters. Love the color your panel is putting out!