DIY COB lightning - need some help

Hy,

I need some help for my COB build. I have a 1 meter x 1 meter tent. It is actually 3.3 feet x 3.3 feet, but some of you is considering it to 3x3. So it is 10.89 ~ 11 square feet vs. just 9. #1 confusion. With witch one should i calculate?

I want to use COB LEDs, Citizen 048 1212 Gen 6, 3500K.
I need max. 50W/square feet, but the old rule is 30-35W.
So if i have 9 LEDs at 1400mA it will give 450W total. At 1050 mA 330W, at 1200 mA 380W. In my opinion i will use Meanwell HLG 1400B driver with dimmer. So i can set my current.

I am on the right track? Is this 9 COB too much?
I wanted to use the DIY COB calculator for citileds, but it isn't working for me. It says, "Enter numbers in the input text fields". But they are filled. Probably the problem comes from the newer Java environment, which i have in 2018 november.

Can someone help me please? I want to replace my 400W HPS, but i want do this in the perfect way! I don't want too less/much light.

You're on the right track. Use an HLG-185H-C1400(4 cobs)and an HLG-240H-C1400(5cobs), A or B version. It's up to you whether you want a potentiometer for external dimming or if you would rather have it be on a screw in the driver itself.

Hook them up in series and bobs your uncle.

Airwalker16 said:

You're on the right track. Use an HLG-185H-C1400(4 cobs)and an HLG-240H-C1400(5cobs), A or B version. It's up to you whether you want a potentiometer for external dimming or if you would rather have it be on a screw in the driver itself.

Hook them up in series and bobs your uncle.

Click to expand...

It could be good with all that extra power if you ever go with a bigger tent, but id never go for that much wattage in a 1m tent. Aw16 got a good idea: splitt to 2 drivers and you can work 2 spectrums. Maybe 4 x3500k/80cri for all-around and 5 3000k 90cri for flowering.

Rocket Soul said:

It could be good with all that extra power if you ever go with a bigger tent, but id never go for that much wattage in a 1m tent. Aw16 got a good idea: splitt to 2 drivers and you can work 2 spectrums. Maybe 4 x3500k/80cri for all-around and 5 3000k 90cri for flowering.

Click to expand...

I'd do 4- 4000K and 5- 3000K if doing 2.

Yes, originally i planned to use 2 drivers. In veg i wanted to dimm all lights to 700 mA, and in flower to 1200-1400.

But can you explain this 2 spectrum more? In this case i will use just the 4 4000K's for vegging and all COBs for flowering? In each corner is a 4000K, and the rest will be the 3000K?

Snypie said:

Yes, originally i planned to use 2 drivers. In veg i wanted to dimm all lights to 700 mA, and in flower to 1200-1400.

But can you explain this 2 spectrum more? In this case i will use just the 4 4000K's for vegging and all COBs for flowering? In each corner is a 4000K, and the rest will be the 3000K?

Click to expand...

That works. Just spread thethem evenlg

The 3000K 90 CRI exist in 2 version:
- 303H6M3-F1 90 CRI below BBL (i can order it from EU)
- 303H5M3-F1 90 CRI on BBL (i can order it just from the US)

What is the difference? And which should i order? I see that the below BBL model has more green peak.

Rocket Soul said:

It could be good with all that extra power if you ever go with a bigger tent, but id never go for that much wattage in a 1m tent. Aw16 got a good idea: splitt to 2 drivers and you can work 2 spectrums. Maybe 4 x3500k/80cri for all-around and 5 3000k 90cri for flowering.

Click to expand...

You said that you would never go for that much wattage in a 1m tent. What would you go for? Honestly i read for days and i can see different opinions.

50w a square foot is on the extreme upper side of whats recomended with todays efficient chips, normally 35w is recommended. The extra 15 w per square foot are difficult to use, it is very easy to get into a situation where you have too much light and the plant wont drink enough nutes and you get deficiencies and bleaching. But for a rigg with dual spectrum the wattage seems fine, especially if you dont turn them up both at the same time.

It seems it is difficult to build with dual spectrum, because i need the BBL type, which i can order from the US.
So my first build will be probably with 3500K 80CRI. It is good for veg and for flower.

So i will need ~ 350W. I can achieve this with 9 COBs running at 1050mA. 9*36=324W. So less heat, greater efficiency.
What do you think? So i am just downgrading the driver.

One more question please if you don't mind. If i want to grow a sativa (for example Malawi) which is like the more lights, the 35W/sqft is enough for her?

If you want to prder from the eu check out @diyled thread. Luminous cobs are cheap and slightly better than similar priced citizen and veros as per cobkits tests. Googling diyleduk should bring up his stores page.

Edit: he doesnt carry any luminous cobs anymore but plenty of other things https://www.diyleduk.co.uk

Thank you, sounds good.

What do you think about this kit?
SCOPE-320 LM301B Led Strip Kit [1m x 1m area]
150-370w built in dimmable driver
3000k

Is this as good as cob diy in the same wattage?

I am thinkig of getting this kit and not need so diy. But i could do it also

That kit uses diodes that are a few percentage better than most cobs so it will definitely thump a sq meter.
Looks like a viable option.

hy

if i may step in with my own setup that i want to build but can't figure it out with the cobs and driver's.
also im from eu and can't find a proper site where i can buy all the goodies to build it.
i have tried to contact COBKITS by email but no anser yet, i saw they are pretty active in here so i will give it a try.

i have a 4x4 tent and was thinkin about replacing my spectrabox pro 5 540W for 9 Luminus CXM22 Gen3 3500K 80 Cri for grow and bloom.
any thoughts or suggestions on this please share.
also cant figure it out with the driver which to pick.

thanks in advance

@janner 5x CXM-22 fit almost perfectly on HLG-480H-C1750 but that's a pretty high voltage rig at around 270V. (Series)

Better to break it up into two drivers and run parallel:
4 on HLG-240-54(A or B)
5 on HLG-320-54(A or B)

Timber Grow Lights.. DIY cobs.
Would suggest browsing their website before deciding.

@shimz thank you very much

when i take the drivers you suggested is it still possible to dim all the cobs at the same time or do you need 2 seperate dimmers?
and why should i do it in parallel and not in series?

@PungentPete thank you for the suggestion.

i looked at the site they have nice kits but its not wat im looking for and also i want to build it my self that fits my tent on my way.
but if that wasn't the case i seriously would be interrested.

Parallel wiring allows you to run a lower voltage circuit. High voltage DC is very unforgiving-it'll kill you easier than AC will. You can run multiple drivers on the same dimming control.

GBAUTO said:

Parallel wiring allows you to run a lower voltage circuit. High voltage DC is very unforgiving-it'll kill you easier than AC will. You can run multiple drivers on the same dimming control.

Click to expand...

Just note that if you pair 2 drivers together you need to get a potentiometer with the Ohms rating of 100/# of drivers.

1-100K
2-50K
3-33K
4-25K
And so on an so forth.

thank you very much

what does that mean..does it mean you can't get the light at 100% lighting?