Driverless AC COB LED build

[ZxcStaz]

I just reread the thread, and I have to thank everyone again for their contributions. There are amazing ideas contained within, and a plethora of knowledge. I'm continuously analyzing the comments and I'm using them to craft this project.
One aspect that drives this creation is heat. Many LED users do not struggle with tent temperature. Unfortunately I find that the temps climb into the 90F range when the lights are on. I am running about 3KW of LED lights in my 10'x10' with more than 500 CFM being aspirated. I am trying to minimize the air exchange so that I can increase CO2 concentration without constant input.
That being the impetus, I'm going to find a way to pull the heat out effectively without using air conditioners. I know that they work well, but there has to be a better way to move and utilize the energy while increasing plant growth.
Damn, I'm beat. "F", I have to continue this later - I'm beat, Good night, and I'll post more soon.
- ZXC

 

[nfhiggs]

I'm going to find a way to pull the heat out effectively without using air conditioners.

Water cooling is definitely the most effective way of doing that.

 

[churchhaze]

I just reread the thread, and I have to thank everyone again for their contributions. There are amazing ideas contained within, and a plethora of knowledge. I'm continuously analyzing the comments and I'm using them to craft this project.
One aspect that drives this creation is heat. Many LED users do not struggle with tent temperature. Unfortunately I find that the temps climb into the 90F range when the lights are on. I am running about 3KW of LED lights in my 10'x10' with more than 500 CFM being aspirated. I am trying to minimize the air exchange so that I can increase CO2 concentration without constant input.
That being the impetus, I'm going to find a way to pull the heat out effectively without using air conditioners. I know that they work well, but there has to be a better way to move and utilize the energy while increasing plant growth.
Damn, I'm beat. "F", I have to continue this later - I'm beat, Good night, and I'll post more soon.
- ZXC

I have a little bit of advice to get the temps down. Undo all the soldering you did, throw the square eggs in the trash, and get some real cobs and drivers. You should probably ask for advice on what to buy before you spend a ton of money and time.

 

[churchhaze]

And once you actually have efficient leds, you'll find the whole water cooling effort to be overkill. Most LED setups these days are so efficient and spread out that passive cooling is sufficient.

 

[wietefras]

Many LED users do not struggle with tent temperature. Unfortunately I find that the temps climb into the 90F range when the lights are on.

That's because those leds are about half as efficient as the ones we normally use here. So instead of about 50% light and 50% heat, you get say 25% light and 75% heat from your electricity. Apart from the waste of (lots of) money, that also heats up your room a lot more.

 

[ZxcStaz]

If we ignore the plants’ conversion of light into carbohydrates, all of the electricity input into a system will be converted to heat. Plants may have a 10% efficiency, but this depends on the species. I do not know the photosynthetic efficiency of cannabis, but for this exercise, we will ignore the reduction in heat produced by the conversion of energy to biomass. With the first law of thermodynamics in mind, let’s “just say” that if 3Kw of electricity is input, it will eventually become 3000J of heat, for every second of electrical transmission. Therefore, using some basic math:

3Kw=3000W=3000J/s C(H2O)=4.18J/g degree3.8L = 1gal 1L(H2O)=1Kg=1000 mL and g q=mCT

q=Joules m=mass(g) T= change in temperature in degrees Celsius

If the reservoir is a 5 gal bucket, then:

5gal x 3.8L/gal x 1000g/L = 19000g

T=q/mC = (3000J/s)/(19000g x 4.18 J/gC = .0378 degrees C/s

.04 C x 60s/min = 2.27 C

This translates to about 2.3 degrees Celsius of temperature increase per minute for the 5 gal of water, if all of the heat is absorbed by the water and none is lost to the system nor surroundings.

Regardless of the amount of light produced from electricity, the heat produced will be equivalent to the input. A 3Kw HPS, HgMH, CFL, or LED will create the same amount of heat. Stating that lights will run cooler is a misunderstanding of physics. An increase in the percentage (efficiency) of electricity converted to light vs. heat may afford a reduction in input power, thus a lower wattage system, but input will equal output. I’m basing this system on 3Kw of input, and trying to move heat accordingly.

 

[churchhaze]

Regardless of the amount of light produced from electricity, the heat produced will be equivalent to the input. A 3Kw HPS, HgMH, CFL, or LED will create the same amount of heat. Stating that lights will run cooler is a misunderstanding of physics

You're preaching to the choir here.

An increase in the percentage (efficiency) of electricity converted to light vs. heat may afford a reduction in input power, thus a lower wattage system, but input will equal output. I’m basing this system on 3Kw of input, and trying to move heat accordingly.

You realize this, yet you haven't come to the conclusion that your 3kW lamp could easily be a 1.5kW lamp or even less by not using garbage LEDs. Then you'd only have to cool 1.5kW of heat instead of 3kW. Duh... 1000W HPS lamps would actually be more efficient than what you built.

You have a major case of cognitive dissonance and it makes sense considering the money and time you've invested into this project already.

 

[churchhaze]

The worst part is that the drivers most people are using are 91-94% efficient with active power factor correction so you really don't have that edge you think you do.

I'm not trying to be downer here, but it also feels kind of good. You're one of those types that just can't take advice and instead wants to come teach everyone else despite clearly not having the same experience. It's a shame too because you're clearly a very smart person.

 

[CobKits]

Yeah I know, I have issues. In my own defense, there was an ideology behind it. The copper has a better heat conductance than aluminum, so if I use thicker Cu, more heat will dissipate and it will run the chip cooler. It was a redundant measure such that if the liquid coolant temperature climbed, I would have a fail-safe. It is more expensive, more difficult to work with, and just bloody ugly, but there is less resistance all around. ...I don't know, I'll let you know how it performs. The only detriments that I can foresee are expense and ease of use.

the amount of heat dissipating out thru the terminals into the conductors is so nominal its likely not even measurable. all the little "advantages" you are attempting to leverage still wont put you close to the efficiency of good cobs and drivers

 

[ZxcStaz]

You're one of those types that just can't take advice and instead wants to come teach everyone else despite clearly not having the same experience.

So, you have tested the AC chips vs. the DC chips and drivers and hold empirical, quantitative data? I would be pleased to know the parameters and procedures so that I could replicate the findings and compare the performance.
I reflect upon Volkswagen's emissions claims, and I question the validity of manufactures statements about their products. You know...9 out of 10 dentists recommend blah, blah, blah... I am the kind of guy that would rather create something myself rather than paying 500% markup.
I see that you also compound your own nutrients from your footnote. Do you use reagents or dry premixes? I also find that the pretty labels and overpriced products are appalling. Theses thoughts about commercial overpricing are the basis for my willingness to deviate from the norm and experiment on my own. As for the monetary investment, I've spent about $300 so far, yet I have learned well worth the price, and I'm having fun too!

 

[CobKits]

Water cooling is definitely the most effective way of doing that.

fundamentally more efficient system design is the most effective way of dealing with heat- dont create it in the first place

 

[churchhaze]

So, you have tested the AC chips vs. the DC chips and drivers and hold empirical, quantitative data? I would be pleased to know the parameters and procedures so that I could replicate the findings and compare the performance.
I reflect upon Volkswagen's emissions claims, and I question the validity of manufactures statements about their products. You know...9 out of 10 dentists recommend blah, blah, blah... I am the kind of guy that would rather create something myself rather than paying 500% markup.
I see that you also compound your own nutrients from your footnote. Do you use reagents or dry premixes? I also find that the pretty labels and overpriced products are appalling. Theses thoughts about commercial overpricing are the basis for my willingness to deviate from the norm and experiment on my own. As for the monetary investment, I've spent about $300 so far, yet I have learned well worth the price, and I'm having fun too!

The majority of us estimate efficiency by digitizing the SPD from the datasheet and using that to calculate LER (luminous efficacy of radiation). With LER and the provided luminous efficacy of source (on the datasheet), efficiency can be calculated. Truncate everything outside 400-700nm and you have PAR efficiency. Once in a while, someone here will send out their lamps to be tested in a calibrated integration sphere to validate (or known down) the calculations from the datasheet and it's usually pretty close.

Your leds do have a datasheet, right?

 

[ZxcStaz]

The majority of us estimate efficiency by digitizing the SPD from the datasheet and using that to calculate LER (luminous efficacy of radiation). With LER and the provided luminous efficacy of source (on the datasheet), efficiency can be calculated. Truncate between 400-700nm and you have PAR efficiency. Once in a while, someone here will send out their lamps to be tested in a calibrated integration sphere to validate (or known down) the calculations from the datasheet and it's usually pretty close

Do you sell or manufacture LED chips?

 

[churchhaze]

I see that you also compound your own nutrients from your footnote. Do you use reagents or dry premixes? I also find that the pretty labels and overpriced products are appalling.

I've been designing nutrient formulas since 2009. I don't think I could ever go back to using premixed formulas. Not everything I have is reagent grade, but I don't think that matters for what I consider more like baking than I do hard chemistry. A little bit of error won't really matter to the plant. It's all salts like calcium nitrate, potassium nitrate, mono-potassium phosphate, magnesium sulfate, FeDTPA, etc etc.

 

[churchhaze]

Do you sell or manufacture LED chips?

No, and I haven't even considered it. I have, however, considered selling nutrients.

The thing is that the majority of LED sellers on this site were originally just members of RIU that decided to start companies, and if they started going shady, people would call them out on it.

RIU seems to be one of the few forums that won't punish people for pointing out bullshit from sponsors. (and believe me, bullshit advertisers get ripped apart very quickly)

 

[ZxcStaz]

Your leds do have a datasheet, right?

I haven't even looked for one.

For what I am planning I'm going to need a lot of wattage. At some point I'll have to redistribute heat. If the cheap chips do not perform, I can easily swap them out for more efficient chips, but I really need the data on the cooling. My new creation is a long-term build, but if I can gain some experience with the light fixtures before I have to install them, I'm doing good.
I'm in the process of building a 18' geodesic dome greenhouse. It is a wooden 2"x4" PT frame with poly carbonate windows. I work on it when I'm not in work, or while tending my garden. I feel like "butter spread over too much bread" at times, to quote Tolkien. I don't know...why can't I just watch TV?
.

 

[1212ham]

I am running about 3KW of LED lights in my 10'x10' with more than 500 CFM being aspirated. I am trying to minimize the air exchange so that I can increase CO2 concentration without constant input.
That being the impetus, I'm going to find a way to pull the heat out effectively without using air conditioners. I know that they work well, but there has to be a better way to move and utilize the energy while increasing plant growth.
- ZXC

What LEDs are you using?

 

[ZxcStaz]

What LEDs are you using?

Hi 1212ham, how is it going?
I have an assortment of lights right now. I have a bunch of the Morsen "2000W" full spectrum units. These have an actual draw of about 350W for each unit. There are also about four lens type 300W units, and these draw about 300W each, but they are generic. I have 4 Morsen COB LED 6000K outdoor spot lights, these units draw from 400W to 600W because I have a few different sizes.
I obtained a plethora of broken units for a song because they were going to be disposed of, and I fixed them. These additional units are positioned, which have various wattage's fill any light gaps. Some of the lights now have partial functionality, but my flowering PAR is on average, throughout the tent- 2.5 feet from the top, at 900umol. I went with all these units because they were basically free except for my time investment to repair them. I have about 5KW of true draw LED's in total, but the assortment affords usage of different units for my various grow areas/stages.
Out of all of my lights I like the LED's the best. I put my double-ended HPS/MH aside, along with the CFL's because my flowers were so much more, like "Geico-more", with the LED's. This is not to mention the hot-spot reduction.
Here are a few pic's of my 5 week bloom plants in my 10' x 10' flower tent. I only have five plants in it right now. I'm hoping to switch out some of the lights with the new units in a few months.

 

[ttystikk]

Do you sell or manufacture LED chips?

Not just one but several of the people trying to help you do.

You got lucky by wandering into one of the very best places to learn about LED agriculture literally anywhere.

And you aren't listening to them.

Maybe we should let you fall on your face while we laugh and point? We aren't like that, but we aren't going to let an amateur contradict everything we've spent years learning the hard way, either.

 

[1212ham]

Hi 1212ham, how is it going?

I worked on the setup today. Got the water cooling running again as temps were high the last couple days. An Inkbird temperature controller starts the pump at 85F/29.5C air temperature and shuts off at 84F/29C. The temp. starts to drop within a minute and dips to about 83F. Water temp in the reservoir is around 72F/22C.

I just purchased (70) - 50watt 110V AC COB LED chips, and I am going to create a water-cooled aluminum matrix to power my 10' x 10' flower tent. This 3.5KW lighting system should deliver optimal PAR while keeping the grow chamber below 85 degrees Fahrenheit.

35 watts/square foot is a common recommendation for high efficiency, white LED. I don't know the efficiency of the old blurple LEDs or the cheap AC cobs, but I think it's somewhere around half of that, so I think you need a lot more than 35 w/sq ft., or 3.5k for a 10x10. Just found this on ebay, 80-90 lumen/watt. My Bridgelux strips are 175.

https://www.ebay.com/itm/Driverless-Full-Spectrum-LED-COB-Chip-Smart-IC-Light-Source-Plant-20W-30W-50W/222891053578?_trkparms=aid=888007&algo=DISC.MBE&ao=1&asc=44040&meid=42e03f9b32e847f0b8d0c6f7408cdedf&pid=100009&rk=2&rkt=2&sd=173206044068&itm=222891053578&_trksid=p2047675.c100009.m1982.

Can you give a link to the chips you bought?

I run 3500k, EB Gen-2 strips with an efficacy of 175 lm/watt. https://www.digikey.com/product-detail/en/bridgelux/BXEB-L1120Z-35E4000-C-B3/976-1732-ND/7907661 https://www.digikey.com/products/en?dc=64113
Here's the datasheet, the kind of information available on name brand LED.
https://www.bridgelux.com/sites/default/files/resource_media/DS131 Bridgelux EB Series Gen2 Data Sheet 20171020 Rev A.pdf