LEDgardener

We need a little more information man ! ^^ depends on the surface, do you have a driver you want to use ? do you need LOAD of power or only running cobs smoothly ?

I'm no expert but you are a tough guy to advice there with those infos you've given !

Got heat sinks for each cob and driving them with 1400mha but not sure which version of the vero 29 is best model b c or d !
I’ll be running hlg 320s x 3 for the 3 different kelvin of the cobs with potentiometers on each driver so I can mix the light

With Bridgelux COBs, usually the letter in the part number indicates CRI, or color rendering index. Taking a brief look at the datasheet for the Vero 29, this seems to hold true. Unfortunately, Bridgelux didn't choose to include very comprehensive spectra on this datasheet, and none of the 90 CRI options ("G") are shown. Usually the higher CRI LEDs tend to have more light in the >630 nm range, which is a region in which plants absorb light very strongly. I will often go for the high CRI "G" or "H" designation when possible for this reason.

Have you considered the V18 series? I have had a lot of success using those COBs. Here's a datasheet for them:

https://www.bridgelux.com/sites/default ... ev%20H.pdf

I've also included a plot I put together from spectra from LI-COR and Bridgelux datasheets. Notice how the high-CRI warm white LED matches the plant's photosynthetic "action spectrum" better than the cold-white, low CRI LED shown.

You may as well run the 'C' cobs - given that they will be close to maxing the driver out and can be dimmed if necessary.
MY only concern would be if the heatsinks could handle that almost 100watts.

The other option would be to add more 'B' cobs or even more 'D' cobs to create a better spread.

I would also stick with a single spectrum or mix 3000K 90cri with 4000k 80cri if you must mix.

Hey man

Could you give us more info on the heatsinks you've got ?

And what 320H do you plan to use ? CC or CV ? how many amps ?

Depends on all that because B, C or D versions don't have the same voltage and it can go tricky if you run let's say a B version at 1400 ma , you'd get a 100.8 W unit
C version at 1400 ma = 72.8W
D version at 1400ma = 51.2 W

Approximately

So well it depends still on your heatsink specs and dimensions of your growing space wether you need lots of coverage or small coverage would be enough, I 'd always advice to get more cobs driven below 70W but that's a matter of budget really.

I’m having custom made heat sinks there 190 mm x 150 mm and 50mm high they should cool between 70-100w I’ll also have a 6” in-line fan blowing directly across the top
I was going to run the hlg 320 x 2 or

I wanted to do a mix of cobs to give a better spectrum of light which is why I was going to use 3 x 3000k at 90cri and then mix 3500 and 4000k at 80 cri so that the 4000k offers a bit more blue

My space is 6ft x 2ft

Well I can't tell you about mixing COBS because I would say there is enough blue in the 3000 / 3500 K already but this is only my dime.

If I were to use 4000K I would use only 4000K for veg and then switch to the 3000's and 3500's.

I myself mixed spectrums with 2* 3000K cri 90 and 1* 3500k cri 90 in a 2ft* 4ft and it was really nice, never could give the full juice to the COBS to run at 80W /COB coz the baby was grown under a shitty lamp from the begining and as soon as I switched, she went into beserker growth and ended up beiing in a too small pot but no way to transplant because 1/2 flowering made.

So I would say you should use the D version or C version depending on the driver you're going to use, wether constant voltage or constant current.

I'm more confident with series wiring with cobs so I would give my advice takin' D versions with an HLG320H-C1400 or C versions with HLG320H-C1050 or else you'd have to get another 3rd driver because of the total voltage of your COBs

If you really need more juice since your heatsinks can handle it even if I'm not sure you will need it, you could always go with 5* CObs on the 320H-C1750

Well, it really depends on how much max juice you want your COBS to spit and the total number of Drivers you plan to get, then you have to do the maths with the Drivers input

ok thanku ill bear it in mind