Veg led vs full spectrum

Grow Lights Australia

Well-Known Member
I know this is an old post, but I'm new to LEDs and I have a question! I was researching some things and came across this post. Seems like some knowledge In here, so here goes nothing.

It seems that nowadays most LEDS are made with a full spectrum of different colored lights, with no ability to switch certain colored leds on and off. Most have a dimmer, but other than that, all the different colors, UV and IR's just stay on, the whole way through the grow. I've only seen a small percentage that offers that type of versatility... Sayhon's SH2000 unit comes to mind, with a UV/IR supplement switch, that cuts them on and off at will. BUT, then again, I'm also not looking at super expensive grow lights!

My particular upgraded China light is 240w; it's basically two 12x12" quantum panels, bolted together with a reflective hood. Together, they are loaded with 360pc of 3500k "sunlight" leds, 200pc of purple leds, and 16pc of UV leds - for a grand total of 576 LEDs across both boards... Each panel has its own driver and has a "bloom booster" switch. The problem is you only get access to the purple and UV leds through the bloom booster, which I was under the assumption only was used during flower.

But since every LED distributor is using them all together now anyways, would I be better just having all 500+ LEDS cranking at once? Or will that not be as effective as the pure sunlight spectrum during veg? I'm so used to MH and HPS, this is all so confusing..... thanks for any input!!!!

(I've attached photos of my grow lights specs and the Sayhon unit i was referring to!)
Hi shotnva777 these types of LEDs can be confusing because you do not always get what the Chinese manufacturers say you are getting! Looking at the advertised spectrum compared to your lights I would want a proper spectograph reading see what the spectrum is really like but I will try to answer your questions anyway.

The "sunlight" LEDs appear to be typical 3500K CRI80 2835 diodes which are nothing special but CRI80 3500K is a good alround colour temperature for growing. The UV LEDs are not very powerful considering the number of them so I would say they are not very efficient. But they would be better than nothing. The "purple" LEDs are confusing because they look like phosphor-coated red diodes which are made by using a 450nm blue pump LED die and then applying a red phosphor to it that spreads the red peaks from 660nm into the far red range. We call these "PC Reds" and we sell them ourselves. They are less efficient but they can add valuable far red to the spectrum. If they are PC Red then that might explain why the Chinese call them "purple" because they convert blue light to red. Perhaps that is their logic but they are a red diode not a purple diode.

We put our full spectrum on one channel because we believe it is not only more efficient and less complex which keeps down costs but because we believe in enhancing the spectrum for the entire grow to maximise growth. There are benefits to UVA and far red throughout the plant cycle and this is easily explained when you consider there is more UV during the vegetative phase outside under the sun in late spring and summer than there is during bloom when it is late autumn. There is also a lot more far red light in sunlight than any LED. Sunlight is 25% far red and seems to work well with the UV side of the spectrum to enhance growth but to reduce internodal stretch from shade avoidance which you would expect when increasing the red to far red ratio. Plants don't tend to stretch outdoors even though there is a large amount of far red and we believe this is due to the addition of UV at the other end of the spectrum.

If it were up to us we would suggest using all LEDs at once throughout the grow. You may need to dim the entire fixture or hang it higher during veg as you will not need as much light intensity during 18 or 20 hours of lights on compared to 12 hours during flowering. Running both channels at the same time will be less efficient because the PC Red and UV diodes are not as efficient as the 3500K diodes but the spectrum would be more complete.
 

shotnva777

Well-Known Member
Hi shotnva777 these types of LEDs can be confusing because you do not always get what the Chinese manufacturers say you are getting! Looking at the advertised spectrum compared to your lights I would want a proper spectograph reading see what the spectrum is really like but I will try to answer your questions anyway.

The "sunlight" LEDs appear to be typical 3500K CRI80 2835 diodes which are nothing special but CRI80 3500K is a good alround colour temperature for growing. The UV LEDs are not very powerful considering the number of them so I would say they are not very efficient. But they would be better than nothing. The "purple" LEDs are confusing because they look like phosphor-coated red diodes which are made by using a 450nm blue pump LED die and then applying a red phosphor to it that spreads the red peaks from 660nm into the far red range. We call these "PC Reds" and we sell them ourselves. They are less efficient but they can add valuable far red to the spectrum. If they are PC Red then that might explain why the Chinese call them "purple" because they convert blue light to red. Perhaps that is their logic but they are a red diode not a purple diode.

We put our full spectrum on one channel because we believe it is not only more efficient and less complex which keeps down costs but because we believe in enhancing the spectrum for the entire grow to maximise growth. There are benefits to UVA and far red throughout the plant cycle and this is easily explained when you consider there is more UV during the vegetative phase outside under the sun in late spring and summer than there is during bloom when it is late autumn. There is also a lot more far red light in sunlight than any LED. Sunlight is 25% far red and seems to work well with the UV side of the spectrum to enhance growth but to reduce internodal stretch from shade avoidance which you would expect when increasing the red to far red ratio. Plants don't tend to stretch outdoors even though there is a large amount of far red and we believe this is due to the addition of UV at the other end of the spectrum.

If it were up to us we would suggest using all LEDs at once throughout the grow. You may need to dim the entire fixture or hang it higher during veg as you will not need as much light intensity during 18 or 20 hours of lights on compared to 12 hours during flowering. Running both channels at the same time will be less efficient because the PC Red and UV diodes are not as efficient as the 3500K diodes but the spectrum would be more complete.
You sound like you know what you're talking about and I kind of thought the same thing. It's not as if the sun is only putting of whatever the 3500k diodes are, ya know?

This morning I decided to add another 100w Phlizon light I had lying around, that has all of the different diodes mixed in. The initial light I was asking about doesn't have a dimmer, so I think I'll just wait to turn on all of the leds from that light during flowering. Not going against your advice here, just thinking about it being too intense.....

By me separating the ballast from the quantum boards and adding heatsink and some fans (not to mention the 30°F air I have pumping into the tent from outside), my temps have hardly broke 75°F with 300w blasting 18hrs a day.... inside of a 2x4ft tent lol. In just ONE day I've noticed significant growth, even decided to do some minor LST'n and supercropping on my biggest baby.

I've attached a photo of the strain I'm running this go around, from a local VA supplier/farm!
 

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shotnva777

Well-Known Member
I also purchased this light last week, for next to nothing. Only did so due to getting the brand new 240w Meanwell Driver out of the deal. But after some research, the board holds a full spectrum of Philips Diodes and IR and I wonder if it could be a better grow light than the White Rose one I have in there now. My only complaint (or worry) I guess, would be the lighting footprint. I love that the White Rose is 24"x12". As compared to this new light and it only being 18"x12"....

Would be nothing, to again, seperate the driver/dimmer onto a control board and add a slab of heatsink on top of the Philips Quantum board! Maybe I can just make one light out of all 4?! Lol!!!
 

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Budzbuddha

Well-Known Member
I also purchased this light last week, for next to nothing. Only did so due to getting the brand new 240w Meanwell Driver out of the deal. But after some research, the board holds a full spectrum of Philips Diodes and IR and I wonder if it could be a better grow light than the White Rose one I have in there now. My only complaint (or worry) I guess, would be the lighting footprint. I love that the White Rose is 24"x12". As compared to this new light and it only being 18"x12"....

Would be nothing, to again, seperate the driver/dimmer onto a control board and add a slab of heatsink on top of the Philips Quantum board! Maybe I can just make one light out of all 4?! Lol!!!
That light’s footprint would be closer to 2x2 in spread.
It follows the same form factor as actual quantum boards - regardless of brand.

For that light , it would serve no purpose to “ mod “ that board with a heatsink - it has a passive design unlike finned heatsinks - it would radiate heat like a hot plate . The driver is mounted on risers and will be fine as-is.

Just get to growing …. :weed:
 

shotnva777

Well-Known Member
That light’s footprint would be closer to 2x2 in spread.
It follows the same form factor as actual quantum boards - regardless of brand.

For that light , it would serve no purpose to “ mod “ that board with a heatsink - it has a passive design unlike finned heatsinks - it would radiate heat like a hot plate . The driver is mounted on risers and will be fine as-is.

Just get to growing …. :weed:
Brother it puts off MEGA heat. I had to heatsink and add fans to the White Rose, as it had my tent temps near 95°F. This one puts off just as much haha
 

Grow Lights Australia

Well-Known Member
It is not surprising that it puts out a lot of heat with a 240W driver because that is a lot of power for one board but it is perhaps closer in form factor to 2x QBs as it has 468 diodes spread across a 450mm x 300mm PCB with a 3mm flat plate heatsink. I think it should be OK as it is but blowing some air on it would make a big difference. It is really suited to a 3 foot by 2 foot space which would give you around 40W per square foot. The 3:2 ratio is the same as the PCB.

Be careful how much wattage you put in there. We had a customer who called us one day and said one of our 500W lights was burning all his plants in a 4x4. We thought it was strange so we paid him a visit and found out he had one of our 500W fixture plus a 600W HPS plus an old 200W blurple LED in his 4x4 tent. No wonder he was burning everything! He had much better results when he removed the other lights.
 

shotnva777

Well-Known Member
It is not surprising that it puts out a lot of heat with a 240W driver because that is a lot of power for one board but it is perhaps closer in form factor to 2x QBs as it has 468 diodes spread across a 450mm x 300mm PCB with a 3mm flat plate heatsink. I think it should be OK as it is but blowing some air on it would make a big difference. It is really suited to a 3 foot by 2 foot space which would give you around 40W per square foot. The 3:2 ratio is the same as the PCB.

Be careful how much wattage you put in there. We had a customer who called us one day and said one of our 500W lights was burning all his plants in a 4x4. We thought it was strange so we paid him a visit and found out he had one of our 500W fixture plus a 600W HPS plus an old 200W blurple LED in his 4x4 tent. No wonder he was burning everything! He had much better results when he removed the other lights.
Yea so far so good, they seem to be eating it up. I'm expecting the White Rose to be more near 150w, with the other cpl hundred bloom LEDS off. Ill keep a close eye on it though. Thank you for all the replies and info!

But yea, I've kinda created a "cool tube" type of solution to my hot LEDs. On top of adding heatsink across the entire top of the quantum boards, I've also added heatsink/fans on top of the White Rose. That light was supposed to have the same "passive designed heatsink" as well, but you could literally cook an egg on it, after an hour!!! It had my tent in the upper 90's! I have cold, outside air blowing directly into the top of the left side of the tent - when the lights are on. Now when theyre off, I pull the outside air tube off the duct fan, so that it stays warm enough during lights off. Its just pulling my houses air when lights are off, because it's getting into then 20's and 30's here now outside and i dont need this tent dropping into the 50's, 40's or worse... I've come to realize that with the lights on, it heats the air coming into the tent EXACTLY 30°f higher than the temps coming in.

Id guess about 50% of the air coming in is then pushed across the heatsink/light, with a seperate fan on the other side, pulling air in the same direction - all which blows out of a makeshift vent, on the right side of the tent. The other 50% of that cool air is forced into the growing area via a second, bigger fan pointing down below, towards the plants canopies. (Tried to post a video, but even 20 seconds was too long, so I just took screenshots of video to show)

Whatever doesn't make it out of the makeshift vent I've created, seems to be exhausted up by the carbon filter In the same general area, which then pumps the hot air outside of the house. Not the prettiest setup in the world, but I think I finally have it dialed in...
 

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