Led Lighting: Sh:t Or Shinola?

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DGP

DGP

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You can ditch the diodes and repurpose the heatsinks and drivers,slap a few quality cobs on the heatsink and turn them into great lights.
Interesting, what size COBs fit? It seems like they would need to be smallish or do you just ditch the reflectors and use the regular size (like 24mm diameter)?

Dee
 
sixstring

sixstring

7,079
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Interesting, what size COBs fit? It seems like they would need to be smallish or do you just ditch the reflectors and use the regular size (like 24mm diameter)?

Dee
Check out growmau5 video on youT,ube,it's called Mars hack.i think he used cree 3590 cobs.every fixture is different but the drivers usually have numbers on them for volts and milliamps
 
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Icemud

Icemud

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Here is what I am talking about. Some clips of a Viparspectra "600 watt" LED system for $169. It calls out as 600 watts (I guess equivalent power to HID???) and it draws 269 watts from the outlet. At best it is a around 340 watts comparable power to an HID. It's coverage area for flower is said to be 2.5 X 2.5 but a 600w HID will cover almost a 4X4 area so 6.25 square feet instead of almost 16 square feet for an HPS lamp and reflector. For the same price a person could buy 3 of the COB assemblies and one Mean Well driver from cobkits.com and have at least 8 square feet of coverage at a higher intensity with better light spread. For less money a person could get an HPS and cover almost 3X the square footage.



Pre-Assemble Light engine and driver from Cobkits:

https://cobkits.com/product/meanwell-hlg-240h-54b-driver/
View attachment 785051
View attachment 785052

Also, look at the spectral output. It looks pretty bad and is missing a lot of light over the visible spectrum. No spec listed on color correctness of the light (but often these ads say "Full Spectrum"). COBs are typically 80 -95 CRI so they look very much like real white light. The 3000k look a little red shifted as they should for a flower light source. But with the Viparspectra when you add mostly red and mostly Blue output with not much in between, you get "blurple" (a weird looking purple that almost looks like visible parts of the UV segment).

On the coverage map they supply it really looks like you would be doing well to get a 2X2 grow area covered as the intensity tapers off very quickly. The advantage to a COB array is the light sources are spread out appropriately for the area they are designed to cover and with DIY you have control of that and fixtures can be built that are even adjustable in regards to spacing.

Attached are spectral charts for Luminous as well as Cree COBs. Also, attached are PDF spec sheets for both those COBs as well.

View attachment 785032
The specs form the add
View attachment 785033

View attachment 785036

Luminous CXM22 Spectral chart:
View attachment 785045

Cree Spectral Chart:
View attachment 785047
Also to point out..

The spec sheet of the Viparspectra says lifetime 100,000 hours which is completely incorrect for their quoted "bridgelux and epiled" Chips. Most Cree SMD's only hit around 60k hours before they lose 20% of their output.

The only LED chips that I have seen have a LM95 (lose 5% of light by X hours) is Osram with a LM95 of 100,000 hours... Which are probably 6-10x more per chip than "epiled" which is equivalent for cheap generic LED chips.

I briefly looked to find the Lumen Maintenance data on the Bridgelux and a quick search did not give the full LM80 rating, however did show that within 6000hours of use, the bridgelux chips lost between 5-10% output.. in 6000 hours..

Just thought this was another "false" fact that these crap LED companies are lying about.

Also, their recommended coverage area must be fore growing wheat grass, because when you look at the par numbers, the very middle 1x1 square is hardly enough light to correctly illuminate flowering cannabis, let alone a 3x3 area.


To note.. the reason why brands like this are popular is they are sold on Am@zon.. and Am@zon has an affiliate program where you can earn money on goods that people purchase. If you go to "Goo#le and type in "top 10 LED grow lights" just about every single page that pulls up in the results, will be pushing brands like Viperspectra, and the almost certain way to know if they are making affiliate money, is 9 times out of 10 they will do a quick product review, show a photo, and then have a link, which brings you to the Am@zon page.

Keep this in mind if you ever are looking for product reviews online... if a page pulls up and links out to a Azon sellers page... chances are they are an affiliate trying to earn a commission.
 
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sixstring

sixstring

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Also to point out..

The spec sheet of the Viparspectra says lifetime 100,000 hours which is completely incorrect for their quoted "bridgelux and epiled" Chips. Most Cree SMD's only hit around 60k hours before they lose 20% of their output.

The only LED chips that I have seen have a LM95 (lose 5% of light by X hours) is Osram with a LM95 of 100,000 hours... Which are probably 6-10x more per chip than "epiled" which is equivalent for cheap generic LED chips.

I briefly looked to find the Lumen Maintenance data on the Bridgelux and a quick search did not give the full LM80 rating, however did show that within 6000hours of use, the bridgelux chips lost between 5-10% output.. in 6000 hours..

Just thought this was another "false" fact that these crap LED companies are lying about.

Also, their recommended coverage area must be fore growing wheat grass, because when you look at the par numbers, the very middle 1x1 square is hardly enough light to correctly illuminate flowering cannabis, let alone a 3x3 area.


To note.. the reason why brands like this are popular is they are sold on Am@zon.. and Am@zon has an affiliate program where you can earn money on goods that people purchase. If you go to "Goo#le and type in "top 10 LED grow lights" just about every single page that pulls up in the results, will be pushing brands like Viperspectra, and the almost certain way to know if they are making affiliate money, is 9 times out of 10 they will do a quick product review, show a photo, and then have a link, which brings you to the Am@zon page.

Keep this in mind if you ever are looking for product reviews online... if a page pulls up and links out to a Azon sellers page... chances are they are an affiliate trying to earn a commission.
can you show us the lm80 test for vero ? or did that come from a diff light co ?
 
BombBP

BombBP

1,367
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Loving the cobs in flower so far.

2018 03 16 134424


You can have a good "blurple" light. One of the first ones I built was blurple. I was just about to switch it out with cobs then decided to overdrive the chips. Running at their rated ma they're okay but if you overdrive them they'll grow weed great.
 
Icemud

Icemud

88
33
can you show us the lm80 test for vero ? or did that come from a diff light co ?
Sure I will google it for you..(you know you could also do the same, not being a jerk, just real).

LM70 (30% loss at X hours) for Vero is reported, by Bridgelux
Bridgelux projects that its family of Vero and VSeries LED Array products will deliver, on average,
greater than 70% lumen maintenance after 50,000 hours of operation at the rated forward test current.
This performance assumes constant current operation with case temperature maintained at or below 85̊C
with a nominal drive current in the Vero and VSeries product datasheet specifications
.
 
Icemud

Icemud

88
33
Just for comparison... A cree CXB 3590 LM90 rating is at 61,000 hours... meaning that at 61,000 hours, the 3590 should lose less than 10% of its output at 61k hours, at 85C junction temp.

Source Cree Data sheets on Lumen Maintenance reports...
 
sixstring

sixstring

7,079
313
Sure I will google it for you..(you know you could also do the same, not being a jerk, just real).

LM70 (30% loss at X hours) for Vero is reported, by Bridgelux
Bridgelux projects that its family of Vero and VSeries LED Array products will deliver, on average,
greater than 70% lumen maintenance after 50,000 hours of operation at the rated forward test current.
This performance assumes constant current operation with case temperature maintained at or below 85̊C
with a nominal drive current in the Vero and VSeries product datasheet specifications
.
Yeah I did search Goofle for a good 10 minutes before I asked you so we went from lm80 to lm70 still not bad but nowhere near cree on specs.and citizen has been caught fudging their numbers as well so as far as I'm concerned cree is still and probably always will be top doggy
But keep in mind with Vero if those numbers are even real lm70 @ 50k hours is for the test current and most diy projects are running below those currents so in reality they should see almost no losses over 7 or 8 years.unless of course you run your shit wide open on a 250mm heatsink haha.
 
Icemud

Icemud

88
33
I looked up Osram Oslon SSL Square white chips, as since last I have looked the rating has actually
Yeah I did search Goofle for a good 10 minutes before I asked you so we went from lm80 to lm70 still not bad but nowhere near cree on specs.and citizen has been caught fudging their numbers as well so as far as I'm concerned cree is still and probably always will be top doggy
But keep in mind with Vero if those numbers are even real lm70 @ 50k hours is for the test current and most diy projects are running below those currents so in reality they should see almost no losses over 7 or 8 years.unless of course you run your shit wide open on a 250mm heatsink haha.

Yea, I agree solid data is hard to find, and generally its company dependent which always should be more reference based than a 3rd party test.. but still data. LM ratings are typically forecasts, based off the measurements of a chip taken usually at least 6,000 hours of testing and some will go as high as 14k hours. Then the "curve" is calculated until a failpoint.. so the LM80, they calculate the time until it hits 20% loss, LM70..30% and so on...

Another fault with the Lumen Maintenance data is that its tempertature dependant, and most of these crappy panels have poor thermal managment, so the Lumen Maintenance gets worse the higher the operating temperature...

Its sad to see all these rebranded LED's get sold at premium prices to new growers, especially those that falsefy their tech specs, which is almost all of the companies... Its why I started getting involved with testing leds, and learning all I could so that I could at least help people make good decisions... and help squash the lies and mistruths... I haven't been keeping up with it lately as other things have taken my time lately but still try to help where needed.. Pretty much why I commented on this thread as I noticed the data specs were not truthful so figured I would add the knowledge...

Its funny how the grow light industry, well at least LEDs have evolved over the years... first it was 1 red, 1 blue chip, then 2 blue, 2 red, then 1w, then 3w, then multi band, then 5w, then full spectrum, then COBs and now Quantum boards using low wattage chips... lol all in probably 5 years..

What I do like with the way the industry is going is most commercial facilities are starting to have their own LED's made for their specific purposes, and the use of LED is breaking away from the traditional HPS type setup (one powerful wattage light overhead) and people are using LED more efficiently and creatively...

I definitely love LED's though... I still have some ideas brewing that nobody is doing yet... but i'm going to keep those for myself for now.. LOL
 
Uckemfup

Uckemfup

73
33
Here is what I am talking about. Some clips of a Viparspectra "600 watt" LED system for $169. It calls out as 600 watts (I guess equivalent power to HID???) and it draws 269 watts from the outlet. At best it is a around 340 watts comparable power to an HID. It's coverage area for flower is said to be 2.5 X 2.5 but a 600w HID will cover almost a 4X4 area so 6.25 square feet instead of almost 16 square feet for an HPS lamp and reflector. For the same price a person could buy 3 of the COB assemblies and one Mean Well driver from cobkits.com and have at least 8 square feet of coverage at a higher intensity with better light spread. For less money a person could get an HPS and cover almost 3X the square footage.

Pre-Assemble Light engine and driver from Cobkits:

https://cobkits.com/product/meanwell-hlg-240h-54b-driver/
View attachment 785051
View attachment 785052

Also, look at the spectral output. It looks pretty bad and is missing a lot of light over the visible spectrum. No spec listed on color correctness of the light (but often these ads say "Full Spectrum"). COBs are typically 80 -95 CRI so they look very much like real white light. The 3000k look a little red shifted as they should for a flower light source. But with the Viparspectra when you add mostly red and mostly Blue output with not much in between, you get "blurple" (a weird looking purple that almost looks like visible parts of the UV segment).

On the coverage map they supply it really looks like you would be doing well to get a 2X2 grow area covered as the intensity tapers off very quickly. The advantage to a COB array is the light sources are spread out appropriately for the area they are designed to cover and with DIY you have control of that and fixtures can be built that are even adjustable in regards to spacing.

Attached are spectral charts for Luminous as well as Cree COBs. Also, attached are PDF spec sheets for both those COBs as well.

View attachment 785032
The specs form the add
View attachment 785033

View attachment 785036

Luminous CXM22 Spectral chart:
View attachment 785045

Cree Spectral Chart:
View attachment 785047
You seem to know a bunch about COBs and I’m having a huge issue with light burn and slow growth but nothing to do with temps. I’ve got the COB setup I pictured below, honestly it has older COBs in it, CREE CXA2530, it’s got 6 COBs, its undimmable and has lenses. My power went off and I had to place my plants in the sun for a few hours, I noticed much more vigorous growth in the sun and once I placed my plants back under the COBs they slowed down to almost unnoticeable growth from yesterday. I had noticed leaf curl and some bleaching on my seedlings even at 75 degrees F. So I had raised it up but to the point I believe it’s almost unbeneficial to my seedlings (45”). I think my light is too intense for my seedlings at almost any height...since there are 6 COBs and theyre undimmable. So today I took the cover off my light and unplugged 3 of the 6 COBs...is this a good idea? Should I just take the lenses off all 6 and leave all 6 on or should I leave the lenses on the 3 and just leave those on? I’m pissed because I bought the WRONG LIGHT, DONT BUY AN OPTIC 6 light anyone...they SUCK! (For seedlings and veg they suck anyway). My plants are two weeks old and small af :( most of the growth came yesterday when I placed them in the sun! Spending so much $ for a piece of shit light is....sad lol
Image
Image
Image

My biggest, nicest looking plant at 2 weeks \/
Image
 
DGP

DGP

1,214
263
Yeah, I don't really know if that is light burn but looks more like nutrient burn. However with COBs spaced that close together why the hell would they use lenses, you just get a bunch of hot spots of intensity. I just posted a low cost entry level veg system that you can build for less than $200 and maybe even as low as $78. They are based on quantum QB120 boards. Have a look. I have seedlings and teenagers under it and I can get real close to the plants and they never burn. With my COB's and no lenses or reflectors I can get flowering plants a few inches away and no bleaching just real fast development. They seem to like being close to the light and the intensity is still less than it is on a sunny day at noon so they seem to be able to take all I can give them.

Link to my thred on QB120's: https://www.thcfarmer.com/community/threads/inexpensive-led-entry-point-qb120.95337/

Below is my veg tent. Lights are not real close here because I want a little more spread of the light right now but have run them as close as 3-4". In the flower room I run the COBs real close when the plants are asking for more light. These cost me $38 each to build and they put out 60 watts true power which is equivalent to about 80 watts HID!
20180414 1042541
20180414 1042591


20180409 043324
 
Uckemfup

Uckemfup

73
33
I think your problem is soil related and not due to your COBs.
So why do they grow so vigorously when i put them in the sun, but basically stop once back inside the tent under my COBs? Could it be a cal mag deficiency? I’ve heard CObs need more of that in the nite regimen? Idk...ima newbie w coco/perlite 70/30 GH nutes
 
Homesteader

Homesteader

3,477
263
Small roots are easy to overfeed and I think that is your issue. Calcium and Magnesium do not seem to be an issue. I would just let them go a bit. The second week of growth is like watching paint dry for me, never fast as the roots are developing.
 
B

budfarmer420

7
3
Yeah you are speaking the truth most LEDs advertise way higher power than they are and the efficiency per watt is actually less than HPS, huge rip off i just ditched my china LED for a nicer one.
 
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