Another LED question, my 1st

[Madman960]

I have not asked any previous questions about LEDs. Playing around on the internet, I found out the manufacturer of my LED makes a 1500 watt COB LED specifically designed for marijuana. It's actually 2 questions: 1) What is the difference between a regular LED and a COB LED? 2) Do I get the same LED or the COB, they are about the same price. Thanks.

Madman

[Madman960]

The most efficient spectrum for growing plants, based on over 5 years of research and testing, outperforming HPS, MH, CMH (LEC), induction, fluorescent, and "white" LEDs in equal wattage tests.
One ideal spectrum for both vegetative and flowering stages eliminates growth stalling associated with spectrum changes such as switching from MH to HPS
True full spectrum ranging from UVA to IR (410-730nm) goes Beyond PAR for ultimate flowering and vegetative plant cycles
Targets not only photosynthetic (chlorophyll / carotenoid) peaks but also: Increases THC, CBD, terpenes, flavonoids, antioxidants / vitamins and pigmentation with UV light Includes near infrared (NIR) light to boost photosynthetic efficiency through the Emerson Effect
Traditional LED arrays tend to mainly operate in blue and red wavelengths, the main wavelengths that activate photosynthesis. However, over-saturating plants in blue and red light puts the plants into a dormant state with high concentrations of oxygen and energy storage molecules. While this may lead to some healthy plants, you’re more often left with immature plants and low yields.CrxSunny LED grow lights are designed to mimic real sunlight to offer a full spectrum of light. This allows your plants to go through photorespiration. This essentially forces your plants to work a little harder, which causes them to want to take in more nutrients from the soil and water. The result: healthier plants and larger harvests.
Strong Hanging Kits are available for Easy Installation
All LEDs with a Zener to ensure One LED Goes Out the Rest Continue to Operate
3 years Long Life Span, Energy Saving and Environmental Protection

[DrPhoton]

That whole text is totally off the track, i got a headache reading it. But thats not uncommon in the grow light industry, i have not come across one manufacturer that understood plant biology correctly.

SMD (Surface Mount Device) Is a single substrate of light emitting diode.
COB (chip on board) is the addition of multiple SMD chips fitted as tight as possible on a circuit board.
It is basically a way of making LED chips brighter for a smaller surface area. Very handy for applications that benefit well from smaller light emiting devices. Such as cell phones or spotlights. Its commonly misunderstood that COB is more efficient than its SMD counterpart. This is incorrect however. Because of the concentration of energy from the many individual light emiting diodes, the heat actually works against efficiency. This is because the junction temperature is relative to a diodes efficiency. This is the main reason of how thermal runaway events happen. Think light blow outs.
The same radiant flux output (total energy) of a COB chip, spread out over a larger surface area with SMD. Will be more efficient because of the lower concentration of heat and higher dissipation.

You might find this thread useful, i detail the most ideal way to build a light source using LEDS.

[Flockshot]

It has been my experience that the guy trying to sell a light will make that light sound like the 'next great thing' in growing. It never happens. A grower's set-up will yield a 'grams per watt' that is pretty consistent if he or she changes from one good quality light to another.
Much of the confusion for growers is intentional, because they are not improving 'grams per watt' they need some reason for you to spend your money.

[Madman960]

Dan and Flock, I am having good results with their standard LED. Going to buy another. Just wanted to know if I should get the same model or the COB version as they are only $3 different in price. COB is cheaper. The COB model is sold from the manufacturer and the standard LED version is sold by the manufacturer and on Amazon.

Happy growing.

Madman

[PRIMO]

Huh ?? Wait what?

[Madman960]

Primo, I have a standard type LED light and found out the manufacturer makes a COB version around the same price. Just $3 difference. I am having good success with the current light and debating on buying another or getting the COB version. I don't understand the difference between a standard double chip LED and a COB LED. I know McCubed is growing well with his COB setup. I have to purchase the COB straight from the manufacturer or I can get the same light I currently have from Amazon or from the manufacturer.

Happy growing.

Madman

[GRAND]

Madman960 ya know, this might be a good opportunity to do a side by side, for 3$ difference, I would try the cob vs what your using now. P.S., I researched your light company a lil last night, I may order a cob light just to see what or if there is a significant difference. take care bro, and happy growing!!

[Madman960]

Grand, That is a fantastic idea. The COB is actually $3 cheaper. The light I currently have is $17 cheaper on Amazon vs buying straight from the manufacturer even though the manufacturer is selling them on Amazon. Their COB is the only LED I have seen that actually says it's made for growing cannabis. I believe their name CRXSUNNY actually stands for Cannabis prescription Sunny. CRX. Makes sense to me anyway. Not sure where they ship from, but says free shipping in the US. I did send them an email asking for PAR ratings. I will post here when they respond.

Happy growing,

Madman

[Madman960]

I heard back from the light of manufacturer. Their specs on the 1500 Watt standard LED is 1164 PAR at 60 cm or 23.62 inches and the 1500 watt COB is 1260 PAR at 60 cm or 23.62 inches. I don't have a PAR meter yet so unable to verify.

Happy growing.

Madman

[DrPhoton]

Single measurements dont tell you much i am afraid.Here is a good article that provides some good pointers.

[Madman960]

Dan, while you may be correct, I posted this because that's also their recommended height above the canopy, 60 cm. I am having good results with their other light. I am going to buy a COB as mentioned by Grand and see if I get the same, better, or worse results. As I only need around 500 PAR for veg, I can probably raise my light more. I originally had it at 40 inches and my nose spacing was very tight. Currently at 30 inches above the canopy. Around week 3 of flower, I will likely move the light back to 22 inches and week 5 to 18 inches. I will post pictures daily after lowering the lights just to make sure I a not causing light stress to the plants. I'm sure 1164 PAR at 24 inches is plenty during flower, I just want to see what happens at 18 inches.

Happy growing.

Madman

[Madman960]

Madman960 ya know, this might be a good opportunity to do a side by side, for 3$ difference, I would try the cob vs what your using now. P.S., I researched your light company a lil last night, I may order a cob light just to see what or if there is a significant difference. take care bro, and happy growing!!

I finally got around to ordering the Cob light a few months ago. But they were also just launching the 1800 watt Contact on Amazon for the same price as the 1500 watt Cob, so I got both. All 3 lights are by CRXSUNNY. Then I did the stupidest thing I could. I added both Cobs to my flower tent and forgot to check them for 4-5 days. When I finally remembered, the plants were toast.

I currently have the 1500 watt Cob over my white rhino cause it is smaller than the Misty Kush so it got the 1800 watt Cob.

When I get home, I am planting my next 5 seeds. 2 bag seed, 1 Chrystal, 1 Aurora Indica, and 1 super skunk. Only doing 1 each cause I only have one seed of each.

Happy growing.

Madman

[Redwasp]

I have never tried cob lights. But can say actual watts used is more important from what ive seen. Led vs hps/mh etc. You can grow great plants with them all. If you fix heat, height, wind, water, etc etc etc.

[gbauto]

Actual power consumed can be a useful metric but after checking CRXSUNNY's website and looking at performance specs listed, the efficacy of ~ 65lm/watt is HORRIBLE. My Vero's and the Samsung F strips are over 160lm/watt-that means that from each watt of energy consumed, your lamp produces 60% more heat than my efficient rigs...I'd pass

[Madman960]

Rw,

All 3 lights pull roughly 300 watts. I won't know yields until I stop killing the plants. I keep debating on getting hps for flower and using my original light for veg. It grows huge plants. I know that other stuff plays a factor. However, if I go that route, I will definitely be buying a 2nd. I would like to finish a grow with the lights I have prior to deciding.