Quantum Boards for Side Lighting

Hey folks,

My buddy has a room with 9kW of DE HPS overhead and a 12 x 12 foot growing area that has 2 foot walkways around three sides and a wider walkway on the last side. He wants to add side lighting. His 4 ton AC unit is already pretty much maxed out with the heat loads already present so we will probably be adding a one ton portable AC unit to handle the LED side lighting heat.

I was thinking that for the side lighting we would use QB324's, each set to cover a 2 x 2 area of the side canopy. So that would be 24 QB324's for a total of 3480 watts of LED. figuring them at 3.5 btu per watt I get 12,180 BTU/hr of just a hair over a ton. So that seems to work out.

My question is if I mount them on the walls 2 feet away from the side trellis, will I get a 2 x 2 coverage area from the QB324?

Also, how many of the QB324's can I run on a single driver if I upsize the driver? Would be nice to run like 6 of them on one driver, that would be 4 drivers, one per each side of his trellis rig.

@coreywebster @ttystikk

QB288's allow way more off a driver unless this is a new model.
Will not go any further but say I think it is an excellent idea!
I am doing same but on much smaller scale.

Well on each side I want to cover an are 2 feet high by 12 feet long. So I figured since the 324's say they cover a 2 x 2 foot area that I could use 6 of those on each side of the room. I just don't know if the 2 foot distance from the light to the plant is going to be correct to get the 2x2 coverage, and should I use lenses? I figure no lenses since the coverage areas will overlap for the most part.

It might be easier and cheaper to just build a strip light ran soft and like only 5 inches away and get direct coverage too

f series said:

It might be easier and cheaper to just build a strip light ran soft and like only 5 inches away and get direct coverage too

Click to expand...

There is no way a strip built light is cheaper than using QB324 boards.
I am staying out of this part.
I am sure those you tagged can help with numbers better than me.

I am not even sure where you can buy single boards with the nichia vers the samsung diodes , does HLG stock them again?

Good luck with your build!

f series said:

It might be easier and cheaper to just build a strip light ran soft and like only 5 inches away and get direct coverage too

Click to expand...

5 inches is too tight a tolerance to maintain and the 2 foot space is used for walking to water plants.

Hey Renfro, yeah one of those boards will cover 2x2 space no worries.

Im not seeing them on HLG site, only on growerslights so I had to find the voltage from here

https://ledgardener.com/forum/viewtopic.php?t=1904

There is a couple of suggestions for driver options, I will have a look when I get back from work tonight and see how it looks for more boards on a bigger driver.

https://growerslights.com/products/horticulture-lighting-group-320-watt-xl-quantum-board-324-led-kit

these are kinda cool to and not expensive anyone have one?
https://www.mouser.ca/new/ilumi/ilumi-meshtek-controller
It talks about it link to boards.

Hope you dont mind OP just trying to learn new stuff.
I have two of these(without the red's)
https://growerslights.com/collections/horticulture-lighting-group-quantum-board-led-kits/products/horticulture-lighting-group-320-watt-xl-quantum-board-led-kit
They kick ass.

Most hang their QBs less than 24" in height so 2ft should be plenty of spread for a 2ft span.

The QB324s that I found are labeled as 18P18S and populated with the LM301B. This equates to needing a 54V driver. (18 × 2.88V = 51.84V)


If you ran (6) QB324's in parallel with a 600h-54 you could get ~100W+ at each board and might be ok without active cooling, but you'd def want a box fan blowing on them if pushing 100W each imo. I run QB304+ at ~142W but have (4) 7cm axial fans per QB keeping them at no more than 112°f. Without the fans theres no way I can push 142W per QB. If I remember correctly I think I was hitting 115f at around 95W (maybe less?) without active cooling, but I can't remember so that figure might be off.


The LM301B is max rated for 200mA, and at that rate the boards would draw over 180W+, so at 100W you're well under max and pretty effecienct at ~105mA each chip.

What he says LOL

I did read something in the QB FAQ section about limiting the voltage to 53.5 instead of 54 to stop heat runaway issues on parallel wired boards. I suspect he will want to drive them pretty hard so we will need to figure out some low profile cooling so we can mount them pretty close to the wall to leave some area to slide in there to water and train plants.

THERMAL RUNAWAY IN PARALLEL WIRED BOARDS
As temps go up the Vf of diodes go down. When Vf does down the diode is able to pull more current. This can cause thermal runnaway in parallel boards circuits if 1 or more boards fail or get disconnected.

HOW TO AVOID RUNAWAY:
1) Use a Meanwell Type A driver if you wire Boards in parallel. Type A driver 54V or under have a Vf adjustment on driver. You can fine tune to limit the voltage. A voltage set at 53V or 53.5V instead of 54V can help avoid runaway.
2) A good thermal design can help. Heatsink can keep the board cool an ensure the voltage of diodes does not go down too much if temperature goes up.
3) Use fuse for each board or thermal cutoff switch.

Renfro said:

I did read something in the QB FAQ section about limiting the voltage to 53.5 instead of 54 to stop heat runaway issues on parallel wired boards. I suspect he will want to drive them pretty hard so we will need to figure out some low profile cooling so we can mount them pretty close to the wall to leave some area to slide in there to water and train plants.

THERMAL RUNAWAY IN PARALLEL WIRED BOARDS
As temps go up the Vf of diodes go down. When Vf does down the diode is able to pull more current. This can cause thermal runnaway in parallel boards circuits if 1 or more boards fail or get disconnected.

HOW TO AVOID RUNAWAY:
1) Use a Meanwell Type A driver if you wire Boards in parallel. Type A driver 54V or under have a Vf adjustment on driver. You can fine tune to limit the voltage. A voltage set at 53V or 53.5V instead of 54V can help avoid runaway.
2) A good thermal design can help. Heatsink can keep the board cool an ensure the voltage of diodes does not go down too much if temperature goes up.
3) Use fuse for each board or thermal cutoff switch.

Click to expand...

Ya honestly you could set it at 52.5 or 53, but the boards won't run away on you because the driver can't flow any more current than max, so even if the Vf drops your driver is stuck at its max already with 6 boards, but you're absolutely right, with CV drivers there is always a potential for runaway, if the driver can accommodate the current supply to facilitate.

how many HLG-240H-C1400B drivers can I put on each channel? 1-10v