So many choices, please help me decide.

[MrFlux]

Do you have any links to help me with my colour/temp/k choice as I wouldnt want to buy 24 of the wrong type, I have searched for knna but only find posts talking about him rather than any information about led colours to use.

Andy here is the relevant KNNA thread. He recommends an absolute minimum 40 umol/s/m^2 of blue light, where blue light for KNNA is between 431-480nm (everyone has his own definition of what is 'blue' so this makes comparisons a bit difficult). According to him some more blue is better to help keep internal CO2 concentration up.

Since you were initially considering the a51 panel, here is a picture to provide some perspective

 

[andyhot]

Hi mr flux.
thanks for the link I will have a good read but fear a lot of it might go over my head.
As for that graph if the area 51 panel is as good as I think it is, then the vero 4k should be ideal as it seems to be better in every way than the xte 3700k.
I was thinking I might need to add a few 2700k along with the 4000k but it seems I was wrong.
Im guessing you think the 4000k is the ideal k if thats what you have bought so I think that might be the way to go.
many thanks for all your help and guidance.
Andy.

 

[andyhot]

Ive also just realised that as a bonus you get an extra 20 lumens for each 4000k chip compared to 3500k. So thats a nice extra 480 lumens overall.
I think you might of convinced me 4000k is the way with that graph.
thanks andy.

 

[Greengenes707]

Andy here is the relevant KNNA thread. He recommends an absolute minimum 40 umol/s/m^2 of blue light, where blue light for KNNA is between 431-480nm (everyone has his own definition of what is 'blue' so this makes comparisons a bit difficult). According to him some more blue is better to help keep internal CO2 concentration up.

Since you were initially considering the a51 panel, here is a picture to provide some perspective

View attachment 2905852

How are those "per 1w input". What Vero is that for(10, 13, 18,29)?

 

[MrFlux]

How are those "per 1w input". What Vero is that for(10, 13, 18,29)?

It's for the Vero 10. The graph shows the umol output per Watt. For example the vero uses 9.35W, so its output is then divided by 9.35. This allows a Watt-to-Watt comparison.

 

[MrFlux]

Andy it was a pleasure. If you are ordering from Digikey you will find the 4000K on backorder. Hope you enjoy your build and would love to see some pictures here!

 

[andyhot]

Hi again mr flux.
I really appreciate you taking the time to help me. Would the above graph scale across all the vero chips or would there be gains to be had by using few larger chips at higher currents. I am working to a budget but if spending a little extra on the larger chips seems worthwhile then I think it could need considering if I can find the appropriate drivers for sensible prices.
you can be sure ill post some pictures when I finally get it all figured out and start building.
Also when you said you plan on mounting your chips on 1m aluminium profile do you mean 1m lengths of heatsink?
many thanks andy.

 

[Greengenes707]

It's for the Vero 10. The graph shows the umol output per Watt. For example the vero uses 9.35W, so its output is then divided by 9.35. This allows a Watt-to-Watt comparison.

I didn't notice you had it in µmols/nm, nice. So is that a graph you created yourself? How/why was 750ma chosen for the XT? Just curious about your analysis system.

 

[andyhot]

Hi greengenes
Hope im not being rude answering your question to mr flux.
I believe it is a graph mr flux compiled to show me how the 4000k vero 10 at 350ma would compare to the cree xte 3700k used in the area 51 panel where they're run at 750ma.
hope this helps and im sure mr flux will correct me if im wrong.
thanks andy.

 

[Greengenes707]

Hi greengenes
Hope im not being rude answering your question to mr flux.
I believe it is a graph mr flux compiled to show me how the 4000k vero 10 at 350ma would compare to the cree xte 3700k used in the area 51 panel where they're run at 750ma.
hope this helps and im sure mr flux will correct me if im wrong.
thanks andy.

All good. That would make sense for the thread and what you were asking about.

I'm just curious because I like what he comes up with, I just want to know how.

thanks man

 

[MrFlux]

Would the above graph scale across all the vero chips or would there be gains to be had by using few larger chips at higher currents.

Yeah the vero family scales linear with size, so per Watt it stays the same.

Also when you said you plan on mounting your chips on 1m aluminium profile do you mean 1m lengths of heatsink?

A normal heatsink would be a bit of overkill so I'm going for aluminium T-profile from the hardware store. It's basically a heatsink with one fin.

 

[andyhot]

Thanks again mr flux you really have been a great help. I will look into using profile but I think with 5 chips mounted on an 80cm length it will get too hot, I did consider using 80cm lengths of 4"x4" aluminium square tube with a 4" pc fan blowing through each one but dont know if it would be adequate. I might just use aluminium u channel and mount some smaller heatsinks on the back side opposite the chips.
thanks andy.