300W LED vs. 400W HID Demonstration

[Propa Gator]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Beautiful mamas, SS. Not quite a travesty to top, but pretty don't go the distance. Soon, you will need to prune every two weeks to keep them, so start now. Think bonsai, and select which little branches you will take later. Flowering is more mechanical than the artsy/fartsy of bonsai mama maintainance. You will soon have much more veg material than you can use, so prune intentionally without mercy or regret. Regret may come later if you don't.
My T5 fixtures are presently doing nursery duty with 6400K tubes kicking butt. When I'm back up to speed with PE, moms can go back under T8s for (slightly) slower growth.
Making new moms later is no sweat, so fugedabout my advice. Genetic change can happen only through viruses. Each 'new' separated plant has the same potential, through beaucoup generations.

 

[go green]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Another thing you could do...to add to propa gator's comment. Dim the lights a little. I have kept moms alive with cheap LED puck lights in a tiny tiny area, with no ventilation, and basically no growth at all, simply maintaining life.

The only problem with methods such as what I just said, is it can eventually make for a sick plant. The roots will need trimmed eventually, and a nice veggie food source, will help it stay well.

+rep Propa! I have seen you around I think...good info!

-Green

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Beautiful mamas, SS. Not quite a travesty to top, but pretty don't go the distance. Soon, you will need to prune every two weeks to keep them, so start now. Think bonsai, and select which little branches you will take later. Flowering is more mechanical than the artsy/fartsy of bonsai mama maintainance. You will soon have much more veg material than you can use, so prune intentionally without mercy or regret. Regret may come later if you don't.
My T5 fixtures are presently doing nursery duty with 6400K tubes kicking butt. When I'm back up to speed with PE, moms can go back under T8s for (slightly) slower growth.
Making new moms later is no sweat, so fugedabout my advice. Genetic change can happen only through viruses. Each 'new' separated plant has the same potential, through beaucoup generations.

I'm going to LST them later today and see how they do with it, but this mom stuff is all new for me.

thanks Gator

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Another thing you could do...to add to propa gator's comment. Dim the lights a little. I have kept moms alive with cheap LED puck lights in a tiny tiny area, with no ventilation, and basically no growth at all, simply maintaining life.

The only problem with methods such as what I just said, is it can eventually make for a sick plant. The roots will need trimmed eventually, and a nice veggie food source, will help it stay well.

+rep Propa! I have seen you around I think...good info!

-Green

It's going to be an adjustment, that's for sure .

thanks Go!

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

I'll probably LST both of them tonight.

They look different from each other, but they've swapped heights and shapes a few times during veg, so not sure if they're different phenos or not.

allright, bedtime for bonzo

 

[astroastro]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Hey SS- great looking mothers for sure. Regarding the potential eye hazards- there is a pretty good paper that describes these issues here

Since LEDs produce no real IR or UV to speak of (unless intentionaly fabricated to do so) we can pretty stick to the visible region of the spectrum- which means we are pretty much talking about the Soret blue bands which are highly reactive with a number of organic molecules. On page 5 of this article they describe this blue light hazard.

The bandwidth required to satisfy the photosynthetic needs of the light harvesting complexes are about smack dab in the middle of the 'danger' curve on page 5. I have a theory on this and how it relates to LED grow lights but maybe too kooky for this forum.

 

[The Lurker]

Plants're starting to look good under those mother f'n hot LEDs there, Sun...

Lurker- thanks for the referral to this journal. More of information like this and less of some of the other stuff and we all might learn what really works with these LED's and what doesn't. Good for everybody...

...Thanks for your post in this forum- I could not and would not disagree with a single word in it.

Well heck astro^2, I'm honored sir. Couldn't have asked for a more ringing (or timely) endorsement than that, especially considering your pedigree.

I just call 'em like I see 'em. If it's good I say so - and if it smells funny, I hold my nose...

And as for the manufactures of LED dies- Philips Semi, Cree, Bridgelux, Seoul Semi, Nichia, etc, etc- all playing the same game with watt ratings. You can see the header at the top of the Philips data sheet- the data as shown assumes a pad temperature of 25C-...You would need some kind of impractical, out of this world cryo cooling unit to keep the pad at 25C. Guess what happens when the pad gets this hot- all of the things you mention in your post!!!

Very true, I see it kind of like the difference between in vitro and in vivo results in biological systems. In the real world you're never going to get a 25C thermal pad temperature, at least practically speaking. The dies are certainly more efficient underneath of that temperature (esp. the reds) since lumen output is on a non-linear curve (or rather, a near-linear curve that is also thermal self-limiting). But it's not good for plants if the room's also -20C!!!

I've seen die tests done where the emitters were intentionally ramped up and cooled with homemade Peltier (TEC) devices; it certainly improved the emitter efficiency (and kept the die from melting!), though not in a total-system sense. (And cranking a 2200 lumen Bridgelux to 4000+ lumens at 205F with cooling is not exactly long-life friendly! )
-----------------

I have thought about DIYing a small unit to try it out, though. These Guys make custom TECs in addition to the standard CPU/GPU ones (you can find them cheaper elsewhere, in standard packages, but the made-to-order stuff is cool - and they'll do small quantities, too). As overall LED efficiency goes up with each manufacturing line introduced into the market, maybe not unheard of in the near future. It would certainly help with all the things we talked about earlier.

(Standard CPU TEC module w/ceramic top/bottom)

Since a good % of what goes to the LED gets converted to light, we're only really concerned with getting rid of the energy that doesn't - i.e. moving enough Deg. C off the die to keep it closer to norms (of maybe a 40-45C difference w/o TEC). That could mean a pretty big jump in lumen efficiency, esp. with reds.

Of course, this means if you're moving, say, ~15W away from the MCPCB, the heatsinks/fans have to get rid of an extra 40-45W+ on the other side (the 15W you removed, and ~25-30W+ from I2R (heat) losses from TEC). So more total power is used, but it reduces/eliminates many of the heat issues from the backside of the actual dies.

Efficient? Probably not. Doable? Yes. Cool? Absolutely! :icon_cool (no pun intended)

From an absolute power (and $/watt) standpoint, it's certainly more practical to use wider spacing between LEDs, bigger heatsinks, higher CFM fans, and simply more LEDs if you want higher PAR, though (but perhaps not higher irradiance within a very small area - which isn't really necessary anyway, IMO. Putting 300-600W in such a small (light board) profile simply wastes energy. Only so much plant biomass can grow into any particular area. See those Mythbusters results...)

An interesting introduction/workup for folks on practical Thermoelectric Cooling for computers can be found. Some nice charts and graphs and a summary on when/whether it makes sense to use them, or not. Same general rules apply to LEDs of course...

If the overclockers can take a 100W+ CPU and keep it under freezing temperature this way, I'm sure mild-to-moderate TEC over a larger area would be useful, too. As long as you take the proper steps to get rid of the extra heat...

Pretty easy to do a modular LED/Peltier setup and then put them together any way you want. Imagine having standard module sizes you can just snap together, and add drivers as and where they're needed. Like high-tech LEGOs for adults!

...now, you run 700mA thru a 1mm^2 LED die and this pad is going to be 'smoking a$$ mother effing hot' (that is an engineering term, don't be offended)....

The red dies (AlInGaP) are much worse in all performance aspects than the blue dies (InGaN)- lots of reasons for this- which I would love to talk about in length, but maybe another time.

He he...I think we've had the same professors. Here's a definition I took directly from my Swipe File (in the Appendix):

(3) A Shitload: According to a reliable source from MIT's Engineering department, 'A Shitload' is a technical term for a quantitative unit of measurement that falls somewhere between 'A Lot' and 'A F**kload'. While not exactly finite, A Shitload is still considered to be quite substantial…

As for the red dies, I figure part of the (non Physics-based) reason is manufacturers have been chasing the 150 lm/w target for white (InGaN phosphor-coated) LEDs for general purpose lighting. Now that Cree's hit that, and that level will become more commonplace in the next couple of years in a lower price point, maybe we'll start to see renewed focus on color LEDs...and adding red LEDs to cooler (CRI-rated) whites to approximate 'warm' white in purpose-built fixtures for the home, using color blending.

The Neutral White (4000K) LEDs have definitely gotten better efficiency-wise (> 100 lm/w) in the last couple of years, also. I'd consider using them instead of cool whites (6500K) in multi-spectrum panels at this point, for many reasons...

Hey Sun- on page 8 you have a shot of the fixture. Well it is a 'b' to get old- I cannot for the life of me determine what kind of LED devices these are- old eyes. Can you post a little closer shot one of these things. I can clearly make out the white LED's (yellow) and that's about it- I cannot make out the device package.

Looks like Sun posted a close-up pic a page or two back, take a look and see what you think. I enlarged another pic from my data files for you; here they are:

First pic is from my files, second is an enlarged version of a package from SS's shot that I digitally enhanced/scrubbed in Photoshop; you can see the copper leads to the individual dies/chips in that one.

Would love to get your thoughts on those, also, astroastro...

...Regarding the potential eye hazards- there is a pretty good paper that describes these issues-

The bandwidth required to satisfy the photosynthetic needs of the light harvesting complexes are about smack dab in the middle of the 'danger' curve on page 5. I have a theory on this and how it relates to LED grow lights but maybe too kooky for this forum.

Thanks also for this paper. Great that we have a nm peak for Chlorophyll that's exactly at its max for photochemical retinal eye damage, too...

Hey mate, no theory is too kooky for this forum! I used to live in Asia and have heard some pretty strange ones myself. No one's going to judge you here. Go ahead and spill the beans--!

(At least, PM me with it if you're still feeling reticent...I'd like to know!)

Cheers,

-TL

 

[astroastro]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Lurker- thanks for the message and the close up shot on the LED package. More on that later. You used to live in Asia!!! I am sitting in China now- Asia is a trip. Oh, and did I mention the girls?

I am familiar with the package style in the photo. But the dies they are using, I am not familiar with. Most of the 1W class dies I have used have had dual die attach pads (a total of 4) at the periphery of the die- the center mounted die attach pad with the bond wire as shown is new to me. I assume the two smaller die attach pads on the substrate are the N (???) terminal attachments to the substrate??? Only guessing here. I gave the shot to a friend of mine that makes LED street lights- maybe he can shed a little more light on what I am looking at here.

A TEC would be a great toy to play with on these LED fixtures. Maybe have some condensation issues that would need to be addressed- but the LED dies would be 'singing in the kitchen'. Probably erase most of the efficiency gains achieved by using the LED in the first place- but you could really get them pumping photons.

Let me play devil's advocate for a minute and reverse your argument for LED die spacing- you are correct in saying that an increase in die spacing reduces thermal density and therefore greatly simplifies cooling- it allows 'simple' brute force cooling schemes based on a chunk of aluminum and a fan. However- on the other hand- extremely close spacing of the LED dies would allow you to 'bend' the Inverse Square Law to your advantage- which would allow you to gain a reasonable amount of spacing between the lights and the canopy with no Inverse Square Law penalty. I have always felt that any light source which had to sit on the canopy (or in close proximity thereof) made daily garden chores a bit cumbersome and that this was a disadvantage to some of the current LED designs out there. This concept would greatly complicate cooling and more elegant cooling systems would have to be designed- maybe your TEC idea could find a home here!!!

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Hey SS- great looking mothers for sure. Regarding the potential eye hazards- there is a pretty good paper that describes these issues here

Thank you for that!

Since LEDs produce no real IR or UV to speak of (unless intentionaly fabricated to do so) we can pretty stick to the visible region of the spectrum- which means we are pretty much talking about the Soret blue bands which are highly reactive with a number of organic molecules. On page 5 of this article they describe this blue light hazard.

Some of the newer LED panels are including IR LEDs. They look like they aren't working when the light is on because they aren't in the visible spectrum. I don't know if UV-producing LEDs are currently being included or not.

You definitely will get "sunburn" from this light if you don't take precautions, and if I don't wear my dark safety glasses, I get an uncomfortable sensation in my eyes after a few minutes of exposure, even from a few feet away.

The dark glasses and sunblock prevent these effects, and I'm now using them religiously.

The bandwidth required to satisfy the photosynthetic needs of the light harvesting complexes are about smack dab in the middle of the 'danger' curve on page 5.

"The highest potential for causing damage is radiation with a wavelength of 440nm. The damage is irreversible and can lead to blindness."

So, we have blue at 440nm, UV, and IR to consider as far as safety.

I have a theory on this and how it relates to LED grow lights but maybe too kooky for this forum.

As kooky as me postulating that plants talk to each other?

I would love to hear your kooky theory, if you would like to share it with us.

again astro, thanks for participating in this journal!

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

I've been following TL's and astro's comments on LED heat management as best I can, and I thought I would throw in a casual, subjective and completely unscientific observation.

To me, the Spectra 300 doesn't seem to run "hot" compared to other lights I've used. The air coming out of the vents on the sides feels warm, but certainly not hot or anything that would make me question longevity issues.

Now, this is an observation made at an ambient temp of around 75F or so, so could be different in hotter weather, but touching the panel and feeling the temp of the air exhausted by the fans gives me the impression that the LED's are being cooled efficiently and effectively.

 

[IrishBoy]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

I've been following TL's and astro's comments on LED heat management as best I can, and I thought I would throw in a casual, subjective and completely unscientific observation.

To me, the Spectra 300 doesn't seem to run "hot" compared to other lights I've used. The air coming out of the vents on the sides feels warm, but certainly not hot or anything that would make me question longevity issues.

Now, this is an observation made at an ambient temp of around 75F or so, so could be different in hotter weather, but touching the panel and feeling the temp of the air exhausted by the fans gives me the impression that the LED's are being cooled efficiently and effectively.

Hey when you took the tent temp reeding did you have your thermometer close to the led units side vents? is so that might effect the rooms temps since all the hot air blows out from their. i can notice a big difference when my meter is close to it then when its on top of my canopy. just wondering about that?

now i think the leds heat up more in hot temps maybe it dosent allow the heat sink to cool down as much since its sucking in hot air?

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

The mom on the right has been looking droopy like that for the last week or so, and slowed her growth down compared to her cab-mate on the left, but it didn't overly concern me.

It should have.

I LST'ed the other mom first and it went well, but when I bent this one over, things didn't feel right. There was no resistance and she was all floppy at the base of the stem. I've never had stem rot on a plant before, and I'm sure it's from the Rapid Rooter combined with my watering technique, so if I use them, I just have to be more careful about keeping water away from them.

What works well for germination doesn't work well down the line for stem health.

Don't know if the poor thing is going to make it. I propped her up and used an eyedropper to put a few drops of hydrogen peroxide solution on the rotted area, but I didn't catch it early and not sure I can save her. If she looks like she's going downhill tomorrow, I may try to take what cuts I can while she's still green, even though she's still not mature enough for that. I can practice with them and/or grow them out somewhere.

Live and learn.

This mom is doing fine, and I'm glad I started two plants.

 

[OldMedMan]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Sorry Sun Seems like we always learn the hard way.
Who would have thought it tho?

 

[astroastro]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

SS- the shot on the stem rot really good- should be in a text book somewhere.

Irish chime in (?)- man- I followed your last grow religiously, got me hooked on this forum- I totally blame you.

Regarding the IR LED's- most of the 1W class IR LED's I have seen are in the 850-950nm peak emission range. Can anyone out there give me a heads up on what response mechanism in the plant we are targeting with this energy? One thing for sure an LED fixture is going to shy of, compared to HID, is energy in the IR range.

An LED fixture is also going to come up short in UV emissions, again, unless this bandwidth is specifically built into the fixture. I have heard as many conflicting stories on the effect of UV on the divine herb as I can count- it increases potency vs. it destroys the plant. I have seen perfectly good product come from greenhouse grown plants, and most greenhouse coverings are fairly effective at blocking UV- this is often a selling point that the makers of greenhouse materials tout- so I am not sure about this. HID lights emit copius amounts of UV (due to mercury emissions), but total UV emissions are regulated by federal law- the outer glass bulb is the final shield so that manufacturers can come into compliance with regulations. UV is high energy stuff, be careful.

 

[Keith Lake]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Can anyone out there give me a heads up on what response mechanism in the plant we are targeting with this energy? One thing for sure an LED fixture is going to shy of, compared to HID, is energy in the IR range.

An LED fixture is also going to come up short in UV emissions, again, unless this bandwidth is specifically built into the fixture. I have heard as many conflicting stories on the effect of UV on the divine herb as I can count- it increases potency vs. it destroys the plant.

HydroGrowLED puts UV LEDs in the mix intentionally; others do as well. The theory can be read here...

Effect of Solar Ultraviolet-B Radiation during Springtime Ozone Depletion on Photosynthesis and Biomass Production of Antarctic Vascular Plants -- Xiong and Day 125 (2): 738 -- PLANT PHYSIOLOGY

I've never heard of any claims that there are any beneficial effects to plant growth in the IR spectrum

 

[dogsnova]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

I've never heard of any claims that there are any beneficial effects to plant growth in the IR spectrum

It's my understanding that the IR spectrum is for speed... Our girls have an internal clock.. IR has a direct effect on this clock...

What I have found is... IR is the least known about spectrum (for growing our girls) but in the future I'm afraid it's going to be one of the most important... Don't kill the messenger...lol

 

[pacard]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

This is a great grow journal! Just soaking up all the good info!

 

[IrishBoy]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

SS- the shot on the stem rot really good- should be in a text book somewhere.

Irish chime in (?)- man- I followed your last grow religiously, got me hooked on this forum- I totally blame you.

Regarding the IR LED's- most of the 1W class IR LED's I have seen are in the 850-950nm peak emission range. Can anyone out there give me a heads up on what response mechanism in the plant we are targeting with this energy? One thing for sure an LED fixture is going to shy of, compared to HID, is energy in the IR range.

An LED fixture is also going to come up short in UV emissions, again, unless this bandwidth is specifically built into the fixture. I have heard as many conflicting stories on the effect of UV on the divine herb as I can count- it increases potency vs. it destroys the plant. I have seen perfectly good product come from greenhouse grown plants, and most greenhouse coverings are fairly effective at blocking UV- this is often a selling point that the makers of greenhouse materials tout- so I am not sure about this. HID lights emit copius amounts of UV (due to mercury emissions), but total UV emissions are regulated by federal law- the outer glass bulb is the final shield so that manufacturers can come into compliance with regulations. UV is high energy stuff, be careful.

lol dont blame me.lol.. thanks for the kind words.

To be honest i dont know too much of the teck stuff about leds but i know most 1w led these days are using 730nm IR led. now its my understanding that IR controls the clock of our plants or the speed, but i have also heard it dose help with resin production.

UV if used the right nm wont really hurt your plant but it will add more resin for sure, its just a fine line between the nm you use and you should only have it on for a little each day. these are the things ive picked up from all the company's lights ive tested. i dont know how true they are? i just like the weed leds grow.lol

 

[IrishBoy]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

It's my understanding that the IR spectrum is for speed... Our girls have an internal clock.. IR has a direct effect on this clock...

What I have found is... IR is the least known about spectrum (for growing our girls) but in the future I'm afraid it's going to be one of the most important... Don't kill the messenger...lol

ya what he said

 

[Setting Sun]

Re: 420 Consumer Reports Competition - GrowLEDHydro 300w LED vs. 400w HID

Good stuff!

I'm in!