Torn between two builds

[Rahz]

I'm still mulling over parts for my next build. There are two basic designs.

1- 6 Vero29s @ 1.4A 42,000lumen

2- 4 Vero29s @ 2.1A 40,000lumen

3- (Which I'm not seriously considering) 6 CXB3070AD @1.4A 46,500lumens

Obviously option 1 is a better lamp with more lumens and efficiency, but option 2 would be cheaper. My main dilemma is how bright the Veros will be at 2.1 amps. Any ideas on hanging height for these lamps? The emitters will be placed in a row illuminating a 2x4' tent.

Any opinions on this?

 

[coolbreez1]

Even at 2.1 amps you can get the Vero 29s up maybe 3 inches away from the top of the cola without any major issues. I would say the issue has more to do with heat generation then light intensity when it comes to them being close to the plant.

 

[churchhaze]

Even at 2.1 amps you can get the Vero 29s up maybe 3 inches away from the top of the cola without any major issues. I would say the issue has more to do with heat generation then light intensity when it comes to them being close to the plant.

Do you have experience with vero 29? Even at 1.4A, at 3 inches from the canopy, it would turn it to a crisp. At 2.1A, there's no way you'd be able to keep it 3inches from the canopy.

 

[Greengenes707]

I'm still mulling over parts for my next build. There are two basic designs.

1- 6 Vero29s @ 1.4A 42,000lumen(42.79% efficiency)

2- 4 Vero29s @ 2.1A 40,000lumen (39.76% efficiency)

3- (Which I'm not seriously considering) 6 CXB3070AD @1.4A 46,500lumens (48.02% efficiency)

Obviously option 1 is a better lamp with more lumens and efficiency, but option 2 would be cheaper. My main dilemma is how bright the Veros will be at 2.1 amps. Any ideas on hanging height for these lamps? The emitters will be placed in a row illuminating a 2x4' tent.

Any opinions on this?

Option #3...seriously.
#3 is 12% more light than #2...and #2 is 8%more that #1. And across the yard... #3, 21% more light than #1.

Small gains in overall efficiency are much larger when looked at as percent gained than it seems sometimes.

 

[coolbreez1]

I am likely wrong... I never measured exactly how close they were to the plants but yes... I do have experience with it, I have two 6 LED Vero 29 lights, with the lights running at 2.1 amps.

I just went back and looked at some of the pictures... I will admit when I am wrong... They were more like 6 inches from the canopy...

 

[Rahz]

Greengenes, agreed on the efficiency, but at these intensities I'm wondering how much light I actually need and whether the extra lumens is worth the upfront cost.

Put it another way in a 2x4'

Option 1 (4 V29s @ 2.1A) 806PPFD
Option 2 (6 V29s @ 1.4A) 856PPFD
Option 3 (6 CXB @ 1.4A) 936PPFD

Thanks for the reference coolbreez.

 

[stardustsailor]

4x Veros 29 @ 2.2 A at 1 meter distance from canopy ( ~39" ) will have a PPF of 593,5 umol/sec ...
At 3" from the canopy will have a PPF of 39/3= 13 => 13^2 = 169 => 169 * 593,5 = 7715,5 umols/sec .

That is 5,14 times higher PPF of the maximum PPF Cannabis Sativa L. species can tolerate .
Which means at 3" from canopy ,it will take about 18-26 hours before the majority of the leaves will be fried for good .
Trust me .(Tested and verified ) .Vero 29 COBs are very-very strong light sources .

One slight difference with the CXA/CXBs, spectrum wise
(Vero29 has more blue & red photons and less green ones than the CXA/CXBs .) ,
at those flux levels makes a big-if not huge- difference .Be cautious with 'em .
At 2.1 A minimum distance should be ~ 22 " (~1,8 ' ) ,between the canopy and the 4 Veros .

Cheers.

 

[Positivity]

I just fried my uppermost fan leaves running a 3590 at 100w within inches... Obviously...Lol..

Wasn't heat either, just light overload. At least it appears, the whole area was fine except for the sun leaves health slowly degrading

 

[AquariusPanta]

I just fried my uppermost fan leaves running a 3590 at 100w within inches... Obviously...Lol..

Wasn't heat either, just light overload. At least it appears, the whole area was fine except for the sun leaves health slowly degrading

Yeah.... 100W... within inches... that'll teach her not to grow so damn tall!

 

[testiclees]

4x Veros 29 @ 2.2 A at 1 meter distance from canopy ( ~39" ) will have a PPF of 593,5 umol/sec ...
At 3" from the canopy will have a PPF of 39/3= 13 => 13^2 = 169 => 169 * 593,5 = 7715,5 umols/sec .

That is 5,14 times higher PPF of the maximum PPF Cannabis Sativa L. species can tolerate .
Which means at 3" from canopy ,it will take about 18-26 hours before the majority of the leaves will be fried for good .
Trust me .(Tested and verified ) .Vero 29 COBs are very-very strong light sources .

One slight difference with the CXA/CXBs, spectrum wise
(Vero29 has more blue & red photons and less green ones than the CXA/CXBs .) ,
at those flux levels makes a big-if not huge- difference .Be cautious with 'em .
At 2.1 A minimum distance should be ~ 22 " (~1,8 ' ) ,between the canopy and the 4 Veros .

Cheers.

Hey SDS,

Are those spacing recommendations based on a cob without a lens or reflector?

I'm using 4 29s at 2.1 mA. They are now between 12-16" from canopy.

Would you please take a look at my spacing and share your impressions?


https://www.rollitup.org/t/led-questions-and-some-more.866506/#post-11484463

 

[Greengenes707]

Greengenes, agreed on the efficiency, but at these intensities I'm wondering how much light I actually need and whether the extra lumens is worth the upfront cost.

Put it another way in a 2x4'

Option 1 (4 V29s @ 2.1A) 806PPFD
Option 2 (6 V29s @ 1.4A) 856PPFD
Option 3 (6 CXB @ 1.4A) 936PPFD

Thanks for the reference coolbreez.

True possibly. Those numbers are all ok though, even in a small area. Nothing negative, "maybe" just a touch of diminishing returns...but over all yield would be a positive gain. Plus the CXB is using less watts to achieve that flux...another small win for the cxb. Extra efficiency means less heat in a small space too. And it's always dimmable if you need.
I have never been truly satisfied with whatever yield I get with leds...always could have been some more somehow with hps and/or a different grower...so till the day that we are actually consistently whooping hps in total yield, I am all about hitting the intensity and light that hps puts out, not being short of it and calling led superior tech that makes up the difference in photons.

You're looking at ~60$ more in cost for chips....then minus 15-20$ because you would use 2 hlg120's instead of hlg185's with cxb vs veros. Upfront additional cost isn't bad...and your light reflects(no pun intended) the additional value in it.

What are you using for the vero to convert to ppfd...3.5ish?

 

[Rahz]

4.88 I wasn't sure where that number comes from so I was using the CXB value for an estimate.

If you could explain where that # comes from it would be appreciated. The lumen output on the Vero V2.0s looks pretty good so I figured it would be close.

 

[stardustsailor]

Hey SDS,

Are those spacing recommendations based on a cob without a lens or reflector?

I'm using 4 29s at 2.1 mA. They are now between 12-16" from canopy.

Would you please take a look at my spacing and share your impressions?


https://www.rollitup.org/t/led-questions-and-some-more.866506/#post-11484463

Yes.No reflector ,no lens.
Right underneath the COBs.

Use of lense and / or refectors do not alter the PPF of the source at a given distance from canopy ,
but the PPFD .(As they concentrate all / most of photons in a " restricted" / "well-defined" area .)

12-16" is rather close .

 

[Rahz]

But yea, torn between 3 builds now. When I was looking at the 6 V29s @1.4A over the 4 @ 2.1 I was thinking, for only a few dollars more. Now that I'm thinking CXB I'm thinking only a few dollars more.

But you're right, the price by PPFD does favor the CXBs.

 

[Greengenes707]

4.88 I wasn't sure where that number comes from so I was using the CXB value for an estimate.

If you could explain where that # comes from it would be appreciated. The lumen output on the Vero V2.0s looks pretty good so I figured it would be close.

When Mr Flux did his cxa analysis thread, he did a lot of calcs for different spectrums from cree and bridgelux and in them were the photon flux. Which is where supra pulled the 4.88µmols/PARwatt for 3K cxa's from. That spectrum hasn't changed with the cxb so it's still good. Flux also calced out the Vero 3K to be 3.49µmol/PARwatt. The vero spectrum did change with the 2.0, so I'm not sure what the conversion is anymore.
@SupraSPL @alesh @MrFlux @stardustsailor Anyone broken down the new vero spectrum into photon flux?

 

[Rahz]

I found the chart I think. Vero 3000K at 80 CRI is 4.94. Are you sure about 3.49? Perhaps I'm looking at something different?

 

[churchhaze]

3.49umol/J PAR certainly does sound fishy just intuitively. With a lower umol/J PAR that would indicate a greater percentage of higher energy photons.

 

[Rahz]

CX series supposedly has a more balanced spectrum, but I'm not sure how that works out overall. Curious what Greengenes will say about this discrepancy.

 

[Greengenes707]

I found the chart I think. Vero 3000K at 80 CRI is 4.94. Are you sure about 3.49? Perhaps I'm looking at something different?

Nice find. I thought the 3.5 was very low...but I never need to use it...cree guy. I think his radiant watts and photon flux got mixed up in his post(which is 3.5w)...because looking again it also has 1.85µ[email protected]%efficiency...which comes to 4.94µmols if work it out backwards.


I swear it is all in his calcs...I just followed along without double checking, shame on me. Pretty sure he just double entered radiant watts for photon flux.

 

[alesh]

Nice find. I thought the 3.5 was very low...but I never need to use it...cree guy. I think his radiant watts and photon flux got mixed up in his post(which is 3.5w)...because looking again it also has 1.85µ[email protected]%efficiency...which comes to 4.94µmols if work it out backwards.


I swear it is all in his calcs...I just followed along without double checking, shame on me. Pretty sure he just double entered radiant watts for photon flux.
View attachment 3394885

Mistakes happen even to the best of us. 4.94 µmol/J is most certainly the correct value.
There's been 3 versions of Veros already, I call them as SDS does -- v1, v1.2 and v2 (you can tell v2 by order code). v1 & v2 have same SPDs in the data sheet (shifted more to red -> higher µmol/J) while v1.2 has different a different one (more Cree-like).