CMH / QB288 / QB120 / SB240 / VERO 29C comparison...

CobKits said:

right but isnt it simpler to say

250 chip board
100W input power

100/250= 0.25W/chip

0.25W / 2.8V = 89 mA/chip

regardless of how the chips are arranged

(obv 2.8V is a simplification but youd still root out the relative info you need)



all of which are up to the user



same with cobs i suppose. nobody is running clu058s at their nominal wattage of several hundred watts

your analogy is more like somebody who buys an (actual) 200W light, one has 4 cobs, one has 9 of the same cobs. caveat emptor on what the difference is

i feel like were saying the same thing in different ways

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we are saying the same thing.

But still the question persists at least 10x per day:
Which is better, the xxxboard or the xxxxxboard?
And it's only going to get worse for the newer diy peeps. I cant swing my dong without hitting 2 new board makers a month.

Growmau5 said:

we are saying the same thing.

But still the question persists at least 10x per day:
Which is better, the xxxboard or the xxxxxboard?
And it's only going to get worse for the newer diy peeps. I cant swing my dong without hitting 2 new board makers a month.

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so.. which is better, the qb304, the qb288, or the qb120?

ganjamystic said:

so.. which is better, the qb304, the qb288, or the qb120?

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which ever is in-stock? oololoo. i like the 288. it has been the most flexible for me personally, offering a wide range of driver combos.

the 304 is really nice for the person who has a set budget today, but wants to invest in efficiency and spread later down the line.
a person could start with (3) qb304 on one HLG-320h-c2800b for a nice 320w setup. (933ma per board in parallel) approx 100w per board. Then, as their budget increases, they could move to (6) qb304 on that same single driver. it would be the same wattage obviously, but now twice the spread, and a massive bump in efficiency.

Growmau5 said:

which ever is in-stock? oololoo. .

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If you were gonna build new lights for your own personal growroom, would you go with cobs or Samsung lm561c pcb? Or if you would prefer something else entirely ?

Growmau5 said:

we are saying the same thing.

But still the question persists at least 10x per day:
Which is better, the xxxboard or the xxxxxboard?

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yes but what we really need to know is how many LEDs to replace a 1000W HPS in a 4x4?

Growmau5 said:

which ever is in-stock? oololoo. i like the 288. it has been the most flexible for me personally, offering a wide range of driver combos.

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i like the 120 for coverage*

*theoretical, have not used

Following along, I'm in the same boat as the OP and LED is just stupidly confusing. Its like the industry doesn't want people to buy them.
Thanks for Cobkits and Growmou5 for contributing. (but please keep it all simple Simon stuff...please..lol)

I agree... while I do find this stuff interesting, and I'm doing my best to understand, I think it's important to acknowledge there are a lot of growers out there who don't have the time, desire, and/or capacity to learn all the technical jargon, but who want the most efficient lights available within their budget nonetheless...

so, for "those guys" , maybe we could try a real world example, and try to keep it in layman's terms...

let's look at say.. a 3x3 for example ... say a grower (great grower, but simple guy..) was used to getting a unit+ per 3x3, but was currently using 750+ watts of 2014-era blurple to do so, thus wasting power and generating excess heat by today's led standards... say this grower was interested in upgrading his lights to something capable of producing the same yield while using less power and generating less waste heat... say this grower didn't have a fixed budget necessarily but was just looking for the most affordable option that would allow him to achieve the same yield while reducing power usage and heat as much as possible... say the grower was considering the following $300ish options.. which would you guys recommend? which would deliver the highest efficiency for that price (µmol/J/$)?

• 315w cmh
  
• 2 qb288s on an hlg-320-54 @ 315w
  
• 6 qb120s on an hlg-320-24 @ 315w

(edit: @Growmau5 and @CobKits ,hopefully I'm not sounding unappreciative here. I'm super stoked to have you guys on the thread and really grateful for your contributions to the discussion.. I respect both of you guys a lot and value your opinions..)

looking at my question above and thinking about it a little more, it seems like 6 qb120s on an hlg-320h-24 makes the most sense.. best spread and the boards aren't driven to max like they would be with the qb288s, am I right? plus, wouldn't it be possible to add 2-3 more qb120s to the same driver in the future for an even greater boost in efficiency?

ganjamystic said:

and the boards aren't driven to max like they would be with the qb288s, am I right?

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reread growmau5's posts about current per diode

CobKits said:

reread growmau5's posts about current per diode

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I tried re-reading like you said, I can't say i 100% understand. But I'll give it my noobie attempt once again so please correct me if im wrong.

Is this driver going to run more then the recommended current through each diode?

CobKits said:

reread growmau5's posts about current per diode

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ok so the qb288 has more diodes than the qb120 obviously, but one is 54V 3000mA max and the other is 24V 2500mA max.. I'm not sure how to factor those specs in to make an "apples to apples" comparison.... lol just tell me which board is more efficient!! I don't even need to understand why, I'll just take your word for it

Unagi said:

Is this driver going to run more then the recommended current through each diode?

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I don't think so.. I already asked. that driver will work

ganjamystic said:

@Stephenj37826 or @robincnn , will an HLG-185H-24 run 3 qb120s in parallel? and will an HLG-320H-24 run 6 in parallel?

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Stephenj37826 said:

Yes and Yes.

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Unagi said:

I tried re-reading like you said, I can't say i 100% understand. But I'll give it my noobie attempt once again so please correct me if im wrong.

Is this driver going to run more then the recommended current through each diode?

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only if you wire it to do such. the board should come with a max current spec'd from the seller. thats how hot you CAN run it. my car can do 120 but i rarely drive it to the max, as its much more efficient at 65.

efficiency is a product of how you choose to operate it

CobKits said:

only if you wire it to do such. the board should come with a max current spec'd from the seller. thats how hot you CAN run it. my car can do 120 but i rarely drive it to the max, as its much more efficient at 65.

efficiency is a product of how you choose to operate it

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that's why I was thinking 6 qb120s @315w (52.5w per board / 60w max) would be more efficient than 2 qb288s @315w (157.5w per board / 150w max)... one option slightly underdrives the boards while the other slightly overdrives them... either way, I know the boards can handle being overdriven because I already built 3 lights consisting of 2 qb288s on an hlg-320h-54a.. I can crank them up to max (~160w per board) without frying the boards no problem... the heatsinks just get hot because they're slate 3 triples.. they don't dissipate heat as well as the newer slate 2 triples...

anyway, so am I right that 6 qb120s @ 315w would be more efficient than 2 qb288s @ the same wattage? or am I still missing something here?...

Unagi said:

If you were gonna build new lights for your own personal growroom, would you go with cobs or Samsung lm561c pcb? Or if you would prefer something else entirely ?

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@Growmau5 has a gag order from ChilLED

ganjamystic said:

that's why I was thinking 6 qb120s @315w (52.5w per board / 60w max) would be more efficient than 2 qb288s @315w (157.5w per board / 150w max)... one option slightly underdrives the boards while the other slightly overdrives them... either way, I know the boards can handle being overdriven because I already built 3 lights consisting of 2 qb288s on an hlg-320h-54a.. I can crank them up to max (~160w per board) without frying the boards no problem... the heatsinks just get hot because they're slate 3 triples.. they don't dissipate heat as well as the newer slate 2 triples...

anyway, so am I right that 6 qb120s @ 315w would be more efficient than 2 qb288s @ the same wattage? or am I still missing something here?...

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youre way overthinking it. either of those setups are going to be almost identical to your plants. just count diodes.

for a given budget how do you get the most diodes so you can in turn minimize watts per diode

its a sixty second math problem if the chips are the same and you know cost of board and number of diodes

CobKits said:

youre way overthinking it. either of those setups are going to be almost identical to your plants. just count diodes.

for a given budget how do you get the most diodes so you can in turn minimize watts per diode

its a sixty second math problem if the chips are the same and you know cost of board and number of diodes

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2 x 288 = 576... 6 x 120 = 720... so 6 qb120s makes more sense because it gives me 144 more diodes for roughly the same price??

as well as better coverage and more area to dissipate heat

see, told you it was easy

CobKits said:

as well as better coverage and more area to dissipate heat

see, told you it was easy

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thank you!

CobKits said:

i believe that unless someone comes along in the board world who has the manufacturing volume and large R&D budget of a large led manufacturer, the discrete diodes will never be as cost effective as mass produced cobs for producing light at a given efficacy.

the one thing boards have is footprint for dissipation. its really hard to justify all that real estate when cobs deliver the exact same light, for cheaper in an off-the-shelf design.Sure they are thermally limited but offset thgat with straight diode count. fundamentally they are the same, there is no level of efficacy that a single phosphor chip can reach that a cob cant

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lol but now after all this discussion of boards, I'm reading this and wondering if a cob based solution makes even more sense... for the same ballpark cost of around $300 per 3x3, could I achieve even greater efficiency with 315w of cobs per 3x3?... come on Cobby, don't let me build out my whole space with boards if you think cobs would be better!