The Chinese Quantum Board Knock Off Builds

Cannademik

Active Member
Would this option work decently and cheaper?
I was thinking about buying 12 of these. Probably run them at 60watts?

and just running them across my space with alum angles, which is 4x8..
and attaching it to these drivers lrs-350-48, maybe buy 2-3 of them?
Looking to get 660 watts. I have already 240 Meijiu light and a custom built 300 watt qb board..
 

Rocket Soul

Well-Known Member
Would this option work decently and cheaper?
I was thinking about buying 12 of these. Probably run them at 60watts?

and just running them across my space with alum angles, which is 4x8..
and attaching it to these drivers lrs-350-48, maybe buy 2-3 of them?
Looking to get 660 watts. I have already 240 Meijiu light and a custom built 300 watt qb board..
Would they fit though? seems like theyre just over two feet. Also seems to come with a heatsink on already.
 

Rocket Soul

Well-Known Member
That could work fine but if i under stand right, three rows of lights per tray? Means youll have to run approx 12 inches between them and 12 inches hanging height. Id maybe try at least 4 rows of lights per tray or 16 total for lower hanging height and tighter between the rows. 16 would also bring your watts up to aroubd 960 which is more or less what people rec.
But its also something you could add on later.
 

Cannademik

Active Member
Okay I, can def do that if I do 4 how should I space them? Will that drive I listed be fine? Seems pretty cheap and you recommend it and If I remember correctly someone on this forum uses it as well.
 

Rocket Soul

Well-Known Member
If you wanna base it on lrs-drivers id go 6 strips per lrs, 3x 350 =1050w total. So 9 bars over 8 feet, if you put one bar per foot approx youll cover your 4x8 and little bit more. You could also make it to 3x 2 foot fixtures with around 1 foot spacing between. Makes it easier to handle. Id guess you would look at hanging height of 8-12 inches.
 

maddmango

Well-Known Member
this light seems good


seems less people buy from bava though, what do you guys think of this light? seems like it has good didoes etc

going to buy a 96"x48"x80 tent and i already have 250w. would 250w + 720w = 970w be good for this tent and like 6-8 autoflowers
Bava made sense for me because of the mixed spectrum and the simplicity of the wireing. Yeah the driver is encased but good air flow from the tops solves this. Make sure you ask 4 channel light and reach out to Awen.
 

ilovereggae

Well-Known Member
Ive been crunching numbers and trying to figure out my best path forward without overdoing it spending wise before I get the rest of my grow super dialed in.

I understand that the 301b are 20% more efficient than the 561c. What does that mean in terms of increase in yield though?

Is it even possible to still buy 288 v1 boards from china? I cant seem to find them on KB or Meiju pages anymore. HLG still has them, and they are close enough in price to the knockoff newer boards that I'm considering just getting some of those instead.

I gather that using chinese boards, you are accepting a slight decrease in efficiency vs better QC'd HLG boards.

If I was to go by the rule of running them at 1/2 max wattage and leverage higher diode count, and say I went for 12 HLG V1 boards vs 12 KB V2s, would the lower bin quality of the KB diodes offset the efficiency gains of them being V2 chips? Trying to understand what this would mean in terms of yield.

Last but not least, after reading through this entire thread yesterday I learned a lot of new things regarding operating temps and RH. The one thing im not sure of still is the height of lights above canopy when running 288 boards @ 60w during flower? Is 12" the goal for best penetration? How much headroom do I need to allow for? Up to 24"?

Thanks
 
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ilovereggae

Well-Known Member
That light is tempting just for convenience sake. The one thing I dont get with those v4 boards though, I thought it was accepted that running UV should only happen in the last few hours of the last few weeks of your grow. Since those are physical switches doesnt that mean those will be on for the full 12 hours if you choose to turn them on?
 

ilovereggae

Well-Known Member
if you keep them off they stay off? why would they stay on for 12 hours
Of course if they are switched off, they will be off.

I meant that if you switch them to the on position, when your timer turns your light on, the UV will be on for the duration. It's all or nothing.

As opposed to having UV on a separate strip with it's own timer that only turns on for the last 3 hours of your lights on period.
 

Greenthumbs256

Well-Known Member
Can anyone tell me if using too much IR or UV at the wrong time can be harmful to a flowering plant? I dont mean a ton of excess of course too much of anything is bad.

I just came across soemthing and it has me wondering and I can't seem to find the right information.

Here's my 4x8, the 2 new boards I added both have IR UV and 660, they are the lm301h and 3500k, it has got me wondering if this is why I'm experiencing a ton more stretch them use too. Plant on the right just went in same time as the new lights, plant on the left is on day 20 of flower.
20191208_191310.jpg20191208_191338.jpg20191208_191323.jpg

Here is my normal growth and stretch and this is how she comes out at the end, I pulled 1.3lb from the one pictured below.
CM190228-190101011.jpg

As you can see I use to be able to judge and manage a nice clean even canopy, but since my switch to LEDs, everything has gotten away from me.

I'm hoping someone can help me around this learning curve bc I'm just not really sure if I should be running the lights softer, or what. But I'd like to have a bit more control then I do now.
 

Rocket Soul

Well-Known Member
Ive been crunching numbers and trying to figure out my best path forward without overdoing it spending wise before I get the rest of my grow super dialed in.

I understand that the 301b are 20% more efficient than the 561c. What does that mean in terms of increase in yield though?

Is it even possible to still buy 288 v1 boards from china? I cant seem to find them on KB or Meiju pages anymore. HLG still has them, and they are close enough in price to the knockoff newer boards that I'm considering just getting some of those instead.

I gather that using chinese boards, you are accepting a slight decrease in efficiency vs better QC'd HLG boards.

If I was to go by the rule of running them at 1/2 max wattage and leverage higher diode count, and say I went for 12 HLG V1 boards vs 12 KB V2s, would the lower bin quality of the KB diodes offset the efficiency gains of them being V2 chips? Trying to understand what this would mean in terms of yield.

Last but not least, after reading through this entire thread yesterday I learned a lot of new things regarding operating temps and RH. The one thing im not sure of still is the height of lights above canopy when running 288 boards @ 60w during flower? Is 12" the goal for best penetration? How much headroom do I need to allow for? Up to 24"?

Thanks
Youre on the right track but i cant really calculate the pricepoints for you. Depends on where you are and what possible trump taxes you mmay pay for imports. Generally speaking and imho: if you go one bin down, double up on diodes at half power, and get the same price as going one bin up for twice the price per dollar: winning move is 2 diodes on half power. There is usually about 10% to win going up one bin or version versus 10% running the diode on half power. But when you run on half power there are other benefits (lower operating temps, higher max wattage, better spread and lower hanging height) which add up next to the efficiency gain. What to do: price out your options. In terms of yield as you mention: there are too many factors other than light that matters for this. You could only really say in terms of light intensity and and spread.

If youre ordering enough boards i would rec meijiu lm561c 2700-3000k 90cri at about 60w a board.
 
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Rocket Soul

Well-Known Member
Can anyone tell me if using too much IR or UV at the wrong time can be harmful to a flowering plant? I dont mean a ton of excess of course too much of anything is bad.

I just came across soemthing and it has me wondering and I can't seem to find the right information.

Here's my 4x8, the 2 new boards I added both have IR UV and 660, they are the lm301h and 3500k, it has got me wondering if this is why I'm experiencing a ton more stretch them use too. Plant on the right just went in same time as the new lights, plant on the left is on day 20 of flower.
View attachment 4433932View attachment 4433935View attachment 4433933

Here is my normal growth and stretch and this is how she comes out at the end, I pulled 1.3lb from the one pictured below.
View attachment 4433934

As you can see I use to be able to judge and manage a nice clean even canopy, but since my switch to LEDs, everything has gotten away from me.

I'm hoping someone can help me around this learning curve bc I'm just not really sure if I should be running the lights softer, or what. But I'd like to have a bit more control then I do now.
Youure getting good growth and most of those plants seem to have ok nodespacing. It does seem like you have a little excess sucker branches and leaves below the screen. Some selective pruning/defo next round? Take fanleaves from the "root" of the branch you dont want to grow much more or try gml topping (removing some of the first leaves from the most apical shoot without actually removing the shoot itself).

IR (or far red): normally leads to stretch but can also result in transition being shorter and thus less stretch. Strain dependent but general advice would be turning far red off. If these are your first tries with these boards wait until it yields before you write this one off.
 

ilovereggae

Well-Known Member
Youre on the right track but i cant really calculate the pricepoints for you. Depends on where you are and what possible trump taxes you mmay pay for imports. Generally speaking and imho: if you go one bin down, double up on diodes at half power, and get the same price as going one bin up for twice the price per dollar: winning move is 2 diodes on half power. There is usually about 10% to win going up one bin or version versus 10% running the diode on half power. But when you run on half power there are other benefits (lower operating temps, higher max wattage, better spread and lower hanging height) which add up next to the efficiency gain. What to do: price out your options. In terms of yield as you mention: there are too many factors other than light that matters for this. You could only really say in terms of light intensity and and spread.

If youre ordering enough boards i would rec meijiu lm561c 2700-3000k 90cri at about 60w a board.
I spent all day yesterday making spreadsheets for comparison sake. I am definitely going to go with 561c chips, as they are definitely the best value.
Thanks for the specifics on the boards to look for. I guess I will contact Meiju for a price directly. Its a dice roll when you try to search Ali for the boards. The same product is listed 3 or 4 times at different prices, from the same company. Very confusing. Shipping prices also seemed the best from KB when they offer the UPS Express option. Only like $40 to ship 12 boards. But I guess I need to contact them about tariffs to see what those would cost. To be honest I am close to giving up and just buying HLG V1 boards as I am weighing the time spent guessing + not knowing exactly what I would be getting from China. Plus seems like if I go that route, I should order at least 1 or 2 spares just in case of failure.

The harder part that I am wrestling with now is finding reasonably price aluminum sheets in the sizes i need (2 boards per 12x18" or 4 boards per 12x48"). It seems that Aluminum is the one thing that is most affected by Trump tariffs. I did find cold rolled 0.125" sheet metal in the 12x18" size for super cheap, but not sure if that is going to be a good enough conductor to keep 2 boards cool running @ 60W? I don't have a garage or tool shop to cut metal down myself, and the price i got back from a local metal shop was only a few $ cheaper than just buying heatsinks w predrilled holes.
 

Zappa66

Well-Known Member
I j
I spent all day yesterday making spreadsheets for comparison sake. I am definitely going to go with 561c chips, as they are definitely the best value.
Thanks for the specifics on the boards to look for. I guess I will contact Meiju for a price directly. Its a dice roll when you try to search Ali for the boards. The same product is listed 3 or 4 times at different prices, from the same company. Very confusing. Shipping prices also seemed the best from KB when they offer the UPS Express option. Only like $40 to ship 12 boards. But I guess I need to contact them about tariffs to see what those would cost. To be honest I am close to giving up and just buying HLG V1 boards as I am weighing the time spent guessing + not knowing exactly what I would be getting from China. Plus seems like if I go that route, I should order at least 1 or 2 spares just in case of failure.
I just made the same calculation and ordered 4 v1288 boards and 4 slate 1 heatsinks from cob kits. Never could manage to pull the trigger on ali.
 
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