Advise needed

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bigstan

Member
Hello, RIU.

I need some help from expirienced LED users. First of all I would like you to look at my spreadsheet and tell me if my calculations are right:

lm = lm/W * W total
eff = lm/W / 325
ParW = W total * eff
mmols/s = ParW * 4.66 or mmols/s = lm / 65

https://docs.google.com/spreadsheets/d/1-ldgF-4SoQvxLS2rok9P0HcOKPjY1mxY2eDZ6KUbxRM/edit?usp=sharing

Feel free to edit formulas.

I was aiming to fit in $200 +/- budget to test LED technology, conversion rate and shipping makes it pretty expensive to buy stuff from USA, but it is the best option right now.

Growing tent most likely will be 60x60 cm or 80x80 cm and will never go bigger, it needs to be stealth'ish.

Electricity bills aren't an issue, it is about $0.04/kWh here, so it will be acceptable for me to run COBs at higher current.

So what do you think will be the best choice? Preferably $200 and lower.
 
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B

bigstan

Member
3rd post

At first I was leaning towards 5x clu048-1212 gen 6 option, there is a pretty good deal on ebay, they selling pack of 5 for about $68. Holders, reflectors, driver, metal and cooling i can buy from local stores.

In the end it will give PPF of 400-450, if calculations are correct.
 
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N

Nutria

Well-Known Member
You're from eu.
On ebay you can find a store called export-estonia selling citizen cobs.
They sell a pack of 5 clu048-1212 90cri gen6 for about 50-60eur.
4 cobs at 1.05A in a 60*60cm tent are good enough.
Driver off tme.eu
You don't need any reflector
 
B

bigstan

Member
Nutria said:
You're from eu.
On ebay you can find a store called export-estonia selling citizen cobs.
They sell a pack of 5 clu048-1212 90cri gen6 for about 50-60eur.
4 cobs at 1.05A in a 60*60cm tent are good enough.
Driver off tme.eu
You don't need any reflector
Click to expand...
That's the deal i was writing about, mainly because it offers free shipping. Also I have found original distributor of Meanwell company in my country, so it will be even cheaper here and shipping is my main concern, because im from Russia.

What's wrong with reflectors by the way? What about lenses? They are not needed because of high reflective material of grow tents?
 
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Airwalker16

Airwalker16

Well-Known Member
Ex
bigstan said:
That's the deal i was writing about, mainly because it offers free shipping. Also I have found original distributor of Meanwell company in my country, so it will be even cheaper here and shipping is my main concern, because im from Russia.

What's wrong with reflectors by the way? What about lenses? They are not needed because of high reflective material of grow tents?
Click to expand...
Precisely.
 
B

bigstan

Member
blake9999 said:
Well first off you will not find a decent LED at your price point. All you will be able to afford is a cheep Chinese knock-off that will not grow good bud.
Click to expand...
I thought 4 COBs of Cree, VeroSE29, cxm-22 or clu048-1212 would be fine for 60x60 cm. Now thanks to getting rid of reflectors/lenses it became even cheaper and all of it fits under 200$!
Keep in mind im counting only cobs+driver+shipping, other stuff is available almost free.

Can you guys tell me if my formulas are ok?
 
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Rocket Soul

Rocket Soul

Well-Known Member
B

bigstan

Member
blake9999 said:
You need Heatsinks, and they cost a little. You have to factor in Everything.
Click to expand...
I'm going to cool my cobs (if i will not change my mind to use boards as Rocket Soul suggesting) with active cpu system, they cost about $5 each, so $25 at max in total, but it is pretty easy to find them even cheaper. Also i have 360mm radiator with pump and reservoir, so it can be fun to cool it with liquid =)
 
GBAUTO

GBAUTO

Well-Known Member
It would be a nice thing to be able to efficiently extract the heat out of the tent. I would try to provide approximately 300W/ m2. You will get better uniformity with more light sources, that's also why I don't use reflectors.
 
B

bigstan

Member
Rocket Soul said:
https://www.led-tech.de/en/ZEUS-308-XT-High-Performance-KIT-3500k
Powered by
https://www.led-tech.de/en/Power-Supply-MeanWell-ELG-150-42A?ref=cl
3500K: full cycle. Also, uses the lm301b, most efficient diode around.
Click to expand...
That's an interesting option, included it in my chart, but VAT makes it 24$ wasted (although that's a price of COB cooling) + shipping is the same as from the USA. I'm in EU geographically, but politically we are competitors, there is a lot of limits, sanctions and taxes.

Also that made me rethink my driver choices for low volume lamps, so it made them even cheaper. As i understand HLG and ELG series are equal in techical characteristics, mostly.
 
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Rocket Soul

Rocket Soul

Well-Known Member
Not quite sure if i understand you, would you get this sent to Russia or EU? Vat should be deductable if sending it outside eu, but youll have to pay whatever taxes and tarrifs you have for import. Same thing for getting something from US, but as there is usual no vat inn s you pay full sticker price, where you should deduct vat from anything from led-tech.de
bigstan said:
3rd post

At first I was leaning towards 5x clu048-1212 gen 6 option, there is a pretty good deal on ebay, they selling pack of 5 for about $68. Holders, reflectors, driver, metal and cooling i can buy from local stores.

In the end it will give PPD of 400-450, if calculations are correct.
Click to expand...
Zeus board should kick the crap out of 400 ppfd, much higher efficiency than clu48-1212. Remember your calculating from spreadsheets on the citizen, the numbers on led tech is real life tests.
Ppfd: 358/0.4 = 895. Usually we deduct 10 % for wall losses= 800 ppfd. Are you sure of your numbers on the citizen, looks low. Maybe you got ppf and not ppfd?
 
B

bigstan

Member
Rocket Soul said:
Not quite sure if i understand you, would you get this sent to Russia or EU? Vat should be deductable if sending it outside eu, but youll have to pay whatever taxes and tarrifs you have for import. Same thing for getting something from US, but as there is usual no vat inn s you pay full sticker price, where you should deduct vat from anything from led-tech.de

Zeus board should kick the crap out of 400 ppfd, much higher efficiency than clu48-1212. Remember your calculating from spreadsheets on the citizen, the numbers on led tech is real life tests.
Ppfd: 358/0.4 = 895. Usually we deduct 10 % for wall losses= 800 ppfd. Are you sure of your numbers on the citizen, looks low. Maybe you got ppf and not ppfd?
Click to expand...
My bad, of course it is PPF, and i'm not sure about those calculations at all. That why i was asking to check those calculations, i got them on this forum.
I live in Russia, sending stuff here. You are right about VAT, it automatically deducted, I was confused with that line though.
If i understand correctly what you did there is PPF / square meters, right?
But how do we calculate PPF if it is not in the description of lamp/cob?
 
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Rocket Soul

Rocket Soul

Well-Known Member
See what happens if you do the whole order until you get to pay, many places will deduct the vat when they see youre youre outside eu.

The only advantage i see with cobs is you can get them in 90cri. Actually if your electric cost is no problem, why not vesta strips? They have dual spectrum 5000k/2700k 90cri. They would spend a bit more electricity but you could play around with spectrum. Also, they are 10$ a strip only and you probably only need about 8-10.
 
GBAUTO

GBAUTO

Well-Known Member
I've used the Vesta's on a hacked King fixture. 90cri and 25w/strip using both the 2700k and 5000k circuits and they rate them at about 125lm/watt. Not great compared to what's available but it was an almost 50% bump in efficiency over the blurple diodes it came with.
 
B

bigstan

Member
According to urbandictionary blurple means blue and purple mixture, correct?

These?
https://ledgardener.com/forum/viewtopic.php?f=11&t=761
https://www.digikey.ca/product-detail/en/bridgelux/BXRV-TR-2750G-2000-A-15/976-1728-ND/7560388

Also about CRI. A lot of people advise to get 3500k 80cri light. I'm not sure if i understood, my english is far from perfect, but is it because 90cri versions are usually lower binned? Or 80 is better for plants in general, although logically it shouldn't be this way if 100cri = sun.
 
Rocket Soul

Rocket Soul

Well-Known Member
For leds 90 cri means more red, instead of peaking in orange it peaks in red wavelength. Some like it, some dont. Usually it gives a little less light, but grows nice
 
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