LED grow lights... input please.

Discussion in 'Indoor Lighting' started by turtle420, Oct 12, 2005.

  1. Indagrojeff

    Indagrojeff Registered

    Induction Lighting Reliability

    Hello all,

    I’m an electrical engineer working for Inda-Gro an Induction grow light manufacturer. I’m a new poster to this site, but I thought it important to comment in areas of technical accuracy. I will refrain from promoting Inda-Gro products and focus only on the accuracy and importance of the post. Please feel free to ask any questions as appropriate.

    First off, I would like to thank KNNA for the excellent postings; they are obviously well educated and versed in the subject manner. I wanted to address the stated issue that while the lamps may have a 100,000 hour life, the drivers do not. I disagree with this comment; if the drivers are properly designed for the application they should not have any issues with this stated life. Electronics generally are very reliable and have extremely long lives. If you look around your own homes I’m sure you can find some items that are 10 to 20 years old and still work just fine. A sweeping statement that the driver in 95% of induction light systems will not meet the life requirements is inappropriate. First and most fundamental is that there is not nearly enough data to support this comment. How could it possibly be clear that 95% will not meet the life statement when there are not any systems that have been in place that long and there certainly have not been so many failures of existing units to base such a statement?

    These products are relatively new to the market, so any failures we are seeing have to be associated with quality and design issues. This is basically the same thing the LED lighting industry went through in the beginning. There are several manufacturers of these products, so you cannot blame the entire industry for what is likely a problem with just a few. Knowing this, it is important to deal with a company that has a strong presence in your country. No product is perfect, failures will happen, that’s just life, the difference is there someone to stand behind the product and take care of you in a timely fashion. Sending the product back to China for repair does not qualify, the country distributor/dealer/manufacturer needs to take care of you as locally as possible.

    Have there been horror stories, I’m sure there have, I’ve heard some. One of our customers purchased an induction light from another manufacturer, the lamp was broken in shipping, both the dealer and the manufacturer refused to help the customer leaving him with a broken lamp that he could not use or repair. Here are my recommendations on this topic:

    1. Do not purchase from a Chinese/Hong Kong drop shipper. They simply are not available to support you.
    2. When purchasing from an in country dealer/manufacturer, make sure they are available to support the product. Ask about their warranty policies and the likely turnaround time of a repair.
    3. Avoid products priced significantly less than similar competing products. There are reasons they are able to sell them cheaper and most of them are not good. That old adage “you get what you pay for” seems to hold pretty well.

    I would like to comment on the general subject of electronics reliability and life since I have a lot of experience in this area. I have worked on NASA, DOD, Nuclear, and life support medical equipment, all of these requiring the highest degree of reliability.

    One of differences today is the wide use of switching power supplies. Switching power supplies currently are the basis for nearly all of lighting industry drivers. Induction, LED, Metal Halide, and HPS electronic drivers are all based on a switching power supply. Switch power supplies have been around for a long time, their main advantage is that they are very efficient, 90 to 95%, where a typical linear power supply is only about 50% efficient. The reason switchers were not adopted earlier, is that they had poor reliability. They are very dynamic, switching at relatively high frequencies, constantly swinging voltage. As with all technologies, they evolve and improve with time, designs are fine-tuned and electronic component reliability has improved as manufacturing process have improved. Today a properly designed switching power supply has an acceptable reliability and life. The problem is that do to the dynamic nature, any design flaw or compromised component will likely show themselves fairly quickly.

    Currently the biggest issue with switching power supplies is the quality of design, components, and manufacturing. We all know that nearly all of this type of manufacturing is currently done in China; we also know that there is a lot of variance in the quality of manufacturers. There are some very good manufacturers, but unfortunately there are some bad that just want to ride on the coat tails of those whom have already done the work. They just want to sell inferior product at cheap prices, often dropped shipped from Hong Kong or via a local dealer/distributor with the same compromised integrity. With these manufacturers and dealers you have a higher probability of product problems and in all likelihood you will have issues with the manufacturer or dealer resolving it. The bottom line is that you need to know who you are dealing with.
  2. brynpav

    brynpav Registered

    lumen output levels etc....

    A little over my head but thanks for your post and welcome to the site.

    you have a schedule on your website Inda-GROthat shows lumen depreciation over a variety of lamps with what appears to be a pretty obvious benefit of the induction lamp maintaining much longer life spans but more importantly at a relatively high average lumen output compared to other lamp types. are we really talking lamps that last that long?

    By your data I was pretty surprised to see how fast all lamps will depreciate but wow do the metal halide fall off fast and I've spent more then a small fortune on re-lamps over the years. :Rasta:

    On another note; have you or possibly anyone else here heard of these new LED's that are organic? They're being called OLED lamps as a solution to the HBLED lamps being too concentrated light output.

    From what I understand they are being coated with a phosphor or polymer to better manage the optical distribution to better diffuse the light and resemble a fluorescent lamp while maintaining color stability in the process.

    I realize this isn't an induction lighting question but then again it appears that if the OLED develops as an option which would completely eliminate the need for any lamp that requires inert gas mixes and Mercury to operate you would be interested in the science behind it.

    If LED mfgs develop OLED lamps that will outperform other technologies then it creates greater acceptance in the marketplace especially of the price points come down as can be expected (Haitz's Law) and the new color quality scale (CQS) is adopted as an updated standard for weighting the hue and saturation levels of any lamp we consider buying.

    Any ideas when the market may be seeing these OLED lamps at competitive prices?
  3. khyberkitsune

    khyberkitsune Registered+

    "Any ideas when the market may be seeing these OLED lamps at competitive prices? "

    Not any time soon. Blue OLEDs have a degradation problem, and the overall lifetime on an organic-based light source is rather poor at the moment. On the same note, output is quite limited.
  4. brynpav

    brynpav Registered

    Are you referring to lumen output or production being limited? Is it fair to say that the main advantages of these newer OLED lamps will be better diffusion and greater color stability of hue and saturation as the market adoption of these type lamps would presumably be more favorable to these improvements. What are your thoughts? Is there any benefit to growers?
  5. khyberkitsune

    khyberkitsune Registered+

    I am referring to the overall radiometric output of the OLED itself. It is not intense enough, and such tiny LEDs will not be bright enough for our purposes, not anytime in the near or foreseeable future.

    Diffusion is not what we want. Photon flux is a ray, and you want more of them packed together, not more of them spread out. This is what we measure, the photon flux density. The more spread out it is, the smaller a plant we are able to grow as we cannot push enough light intensity far enough.

    The whole reason for OLED is as an LCD screen replacement, nothing more, really. Lower power requirements plus a very tiny form factor (and dot pitch) makes it ideal for displays of all shapes, sizes, and resolutions.
  6. canniwhatsis

    canniwhatsis Registered+

    I can attest to this! ;) Even tho I'm an unscientific "Garage grower" (well basement, but what ever ;) )

    I'm doing a side by side HPS LED flower totally separate environments, both same strain, started at the same time.

    Sure my HPS is going to give me a higher overall yield (Even tho I f'd up and double dosed that plant with nutes resulting in a lockout that she's still recovering from)

    But the G/KWH into each grow, the LED (120w) is going to SMOKE the HPS! (600w)

    Plus there does seem to be a slight difference in quality....... The strain is Blueberry, and every one I've pulled under the HPS has been sweet smelling, slightly citrus, with just a "hint" of skunky....... Under the LED when you put your snoot right in the bud it smells like a bowl full of berrys! :eek: :cool: :pimp: I can't wait for the smoke off of this experiment.
  7. Indagrojeff

    Indagrojeff Registered

    Hi Brynpav

    A little slow getting back to this forum so forgive me any delays as I've been pretty slammed.

    I'll respond in the order you've questioned. The lumen deprecation schedule we provided does make a pretty good case for the average lumen output of these lights being above 90% until the 70,000 hour mark whereby it then will gradually fall to the 70% mark at around a 100,000 hours.

    As to the OLED question I have some opinions of this technology but would differ to khyberkitsune who looks to have a deeper background in LED/OLED development. However there does appear to be a field of research devoted to seeing the OLED lamps used in high output area lighting applications.

    I would refer you to a recent article in the October 2010 EC&M, that discusses the high output advantages of OLED technology which may someday be of some interest to the botanical market but it's certainly way to early to tell what if any those applications may be.

    Thank you for your comments.
  8. knna

    knna Registered+

    I do not work with induction lights, so I would like to be drastic about their technical performance. I depend on this of what engineers working in the field tell me, not of first hand experience.

    For what I understood, induction ballast problem is not due to converting AC input to energy used by the induction unit. This is managed by many electronic converters today at very high efficiencies. For long lives, only when spending on it, most Power Supplies expected life strongly depends of operating temperatures. When working on hot environments, as usually ballast on induction lights do, if you dont use expensive components, likely average life is well below 50Kh, often just 20Kh.

    So PS life is strongly dependent of components used, and as far as I know, no any horticultural lamp in the market uses high quality, hot temperature rated components. Although technically possible, I have solid doubts any induction light on sale currently for the horticultural market use a PS with an actual expected life over 50Kh. Just a guess, but I believe that actually, majority of them are way shorter.

    The main problem for induction lights, for what those working on them told me, is the low coupling efficency of coils used on the own induction process. Very low, with very high losses, minimal 25%. This seems to be the main problem and what lead to the big manufacturers to give up with this technology and follow other research paths. Those losses mean lots of heat, and heat is always a problem for reliability.

    I agree with you that properly designed and built induction lamps may have its place and could be an excellent solutions for many cases. But market push for lower prices hard, and in this situation is not easy to offer it. Usually you get what you paid for, and I think most people are not willing to pay what a good designed and build with high quality components induction lamp cost
  9. khyberkitsune

    khyberkitsune Registered+

    We could easily fix induction lighting losses if we could find a proper diamagnetic back shield and design a linear induction tube with waveguides built into the glass.

    The ballast, on the other hand, yes that's not happening any time soon. Cheap market is most definitely the reason for this.
  10. khyberkitsune

    khyberkitsune Registered+


    Aren't you housebroken???
    Last edited: Feb 17, 2011
  11. clongo

    clongo Registered


    im trying to part out two arrays with the best ppfd per watt for one with 12000k, 425 nm 440nm and one with 630nm and 660 nm. I don't know anything about heat sinks needed per diode or how to run them for maximum life while still getting a total of 1500ppfd on a 2.5x3 cabinet scrog. looking for bud depth layer (not starkly pruned below) of 2-2.5 to feet. I think a combination of lenses 90 and 60 degree would be good but I have no idea.
  12. Colorado Grower

    Colorado Grower Registered

    You can get a great deal on LED grow lights at
  13. khyberkitsune

    khyberkitsune Registered+

    You're not telling us where you want that 1500 PPFD. How far away from the light do you want that sort of intensity? A good new 1,000w HPS will put that out about 2-3 feet away, which means 1-1.5 feet from the bulb you're hitting bleaching levels of photons.
  14. silent leprechaun

    silent leprechaun Registered+

    Hey guys,
    I am becoming a big fan of LED lighting.
    I have started my first ever LED grow log.
    You can find it on here or on my word.press page. I update both together.
    I am using a Pro-Grow 260 and 4 x 20w CFL. The CFL are just for heat purposes.
    Have a look and let me know what you think. Hopefully the bloom will go ok. I hope so.

    Here it is: LED LOGGER

    You can find it here under LED grow log testing the Pro-Grow 260

    I hope you enjoy it. I will be blooming in just 5 days from now.

    Ill give the plants 36 hours of darkness to kick start them into the phase.

    Let me know what you think.

    Take care.
  15. Psyz

    Psyz Registered

    Thinking Outloud.....

    Hi all, long time reader but first time poster. First of all thanks to all the regular poster, weezard, oldmac, headshake etc…I have just spent the last week looking over this thread and others. For some time I have been an outdoor grower but due to changing living arrangements this is no long practical so I’ve decided to make the move inside. My major concern with indoor growing is the substantial amount of power required, particularly when I have worked hard to minimise power draw elsewhere in the house; which has lead me to the idea of using LED’s. I was hoping to do a little thinking out loud and hope some of the experts can offer some advice bearing in mind this is just the beginning of a long learning curve for me…Thanks in advance!What I’m hoping to do is connect a 200-300watt solar panel to set of deep cycle marine batteries. These batteries will be charged with a Hybrid MPPT Controller that can provide charging via AC when the sun isn’t shinning.

    From these batteries I hope to run a DIY LED light that I hope to learn to make in the coming months. One of the greatest struggle has been trying to determine the best ratio of red:blue from many different sources. The diodes I’m thinking of running are:
    RED: 625nm
    720nm (Possibly?)

    BLUE: 460nm

    I hope to have these lights running on dimmers so I can use the same light for veg and flowering and the total power use to be around 150-200W. What ratios would the experts recommend, 7:1 Veg 1:4 Flowering? Also I hear many different recommendations for diode wattage some say 1w is better others 3w others 15watt. I’m currently leaning towards the 15watt Weezard approach.
    Once iv decided on wattage I can work on sourcing a heatsink, some PC fans with temp sensor and some drivers. While researching drivers I came across an article on instructables that provides a guide to making a constant current source for powering LED’s…What do you think (just realised turmoil had the same idea? Its all jibberish to me at the moment but I hope to brush up on my electronics theory in the near future.

    I apologise for the long winded approach, iv been smoking and thinking about the idea too much and needed to put the sloshing around quires and ideas on paper. Thanks for taking the time and happy growing ;)
    • Like Like x 1
  16. maruid

    maruid Registered+

    I have a buncha LED bulbs at my house for general lighting. most of them i ordered from dealextreme.com or meritline.com big purverors of china manufactured products. just search "led bulb" on either site. I cant even grow a front lawn, by no means do I have a green thumb but i see issues with LEDs because

    A - they are COLD, they dont seem to generate any heat at all, and if i recall correctly plants need heat (unless there is another heat source, but in nature the light source is the heat source)

    B - Manufacturing consistency. I have ordered lights in groups and individually, it dosen't seem to matter. I can tell different "batches" make different light

    my 2c - maybe worth less :)
  17. mmjman

    mmjman Registered+

    I guess what you did not realize is NASA actually uses LED's on the space station for all horticulture experiments.
  18. Douglas1

    Douglas1 Registered+

    I just bought two blackstar 240's completely on accident.. so, hopefully once I can, I'll have a pretty interesting grow log.. coupled with my other 240 flowering. I know they are not the best, but 300 some watts of pure led light is going to make something happen growth-wise regardless
  19. Native¥organicfarmer

    Native¥organicfarmer Registered+

    About to purchase my second set of led ...........
    works great love them they supplement my 8khid/hps nothing compares.....
    choosing higher quality units looking for 240..... voltage ...

    hell i figure my growing my own medication has gone to far......way to much money...new post.....
  20. pipesdaddy

    pipesdaddy Registered+

    Thw word is convenience. You should pick up the things which is comaptible with your test.

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