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LED - Someone hold my hand

I am old school metal halide / high pressure sodium.  Lost a ballast this past year and it is about time to replace bulbs all around.  So it would be a really good time for me to make the plunge into LEDs.  Problem being, there seems to be no standard in replacing lets say a 1000 watt HID light with LEDs.  Every LED manufacturer has its own way of rating and comparing.

Could folk dumb this down for me?  Tell me what you bought, how well it works, how much coverage it provides.  Even telling me what models you bought when you were disappointed with the results will help me figure this out.
 
Hey Drew. For what its worth Ive trialed about half dozen different units from Ali ranging from 216W to 1200W (60W - 270W real power). The one Im using currently is a 1200W variable so does 40W - 270W and its set at 180W on a 16/8 light cycle.

All of the units worked well and Ive found a happy medium of 120W - 180W for 16sqft. Any more than 240W in 16sqft at 80cm to top of leaves and scalding occurs.

Another observation is that peppers, passion fruit, herbs all grow great but for some reason the likes of tomatoes do not do well. Seems like broad leaf ok and not broad leaf not ok. Its weird.

Ive supplemented my red blue with an additional 20W of cool white floodlight to up the green yellow a bit also.
 
austin87 said:
3 of those 1200W will draw about as much power as a single 1000W MH/HPS
 
That brings me to my next question.  You can not really convert watts to amps without a power factor.  Goofing with the online calculators, I get 5 amps to 20 amps.  How on earth do I calculate how many amps I need to power the things?

My grow room has three 15 amp circuit breakers, but the wire on each is rated just fine for 20 amps.  Changing the circuit breaker is nothing but a thing.  Without worry about heat, if they will run under 10 amps I think it would be cool to grow in my office too.  Mostly for the emotional / psychological benefit of being around plants during the winter.
 
 
P=VxI

So

I=P/V ... I = 280W / 110V = 2.55A (1200W is about 280W real power)

Assume pf of 0.95 ... 2.55 / 0.95 = 2.68A per unit
 
austin87 said:
LEDs are going to run much cheaper than MH/HPS. I've had my eye on these https://www.amazon.com/dp/B01JLKUA2W/ref=dra_a_rv_mr_ho_xx_P1400_1000?tag=dradisplay-20&ascsubtag=34fefc8ff985bcc722d1a64c8bc3541a_S&th=1 as well as some stuff from Roleadro.

3 of those 1200W will draw about as much power as a single 1000W MH/HPS
 
This is inaccurate especially for the Chinese LEDS.
 
The Chines LEDs put out about 100 lumens/watt or less, way less efficient than either MH or HPS
 
If you buy Cree LEDs, it's way better, but they are not inexpensive.
 
Before you buy any lamps from China of any kind, check the lumens/watt.
 
willard3 said:
 
This is inaccurate especially for the Chinese LEDS.
 
The Chines LEDs put out about 100 lumens/watt or less, way less efficient than either MH or HPS
 
If you buy Cree LEDs, it's way better, but they are not inexpensive.
 
Before you buy any lamps from China of any kind, check the lumens/watt.
I think he meant run as in, operate with less electricity used.
 
AndyW said:
I think he meant run as in, operate with less electricity used.
 
Yes, ^ this is correct. Actual power draw of an LED is much less than the stated wattage.
 
willard3 said:
 
This is inaccurate especially for the Chinese LEDS.
 
The Chines LEDs put out about 100 lumens/watt or less, way less efficient than either MH or HPS
 
If you buy Cree LEDs, it's way better, but they are not inexpensive.
 
Before you buy any lamps from China of any kind, check the lumens/watt.
 
When was the last time you tried some Chinese LEDs? I don' t mean to be an ass, just genuinely curious. I haven't tried them myself but I've been keeping loose tabs on the market for the last 10 years. By all accounts, the technology has gotten magnitudes better and the cost has gone down significantly. Chinese manufacturers are definitely making better products than the first LEDs available.
 
Also, if you get something like this https://www.amazon.com/dp/B075GDN3Y9/ref=twister_B075KFVD9P?_encoding=UTF8&psc=1 for $132 vs something like this https://www.amazon.com/Advanced-Platinum-P600-12-band-Grow/dp/B00NTC2XRO/ref=lp_10321450011_1_1?srs=10321450011&ie=UTF8&qid=1509297514&sr=8-1 for $659 and you get 75% of the light power for less than 1/4 of the cost, I'd call that a good deal and buy a couple more of the cheaper ones.
 
The most important things to watch for when shopping for LEDs, are spectrum charts, par maps and actual power draw. If the company doesntnprovide charts, then they obviously didn't even test their design and they're selling the cheapest product they could make.

Yes, the power ratings can be confusing because the LEDs tend to be under driven to produce less heat and longer service life. On top of that some companies claim LEDs are anywhere from 3 to 5 times as efficient for growing compared to hid lights, when they are generally only twice as efficient when using full spectrum white LEDs and about 2.5 times with focused multiple bands that target the par spectrum. Looking at the lumens/watt is a pretty rough estimate for rating LEDs since lumens are related to human vision, an is quite a bit different than par values.

I'm only running a little 45 watt unifun panel from amazon right now, and my plants are still a ways away from flowering stage, so I don't know yet if it will be enough to make them set fruit or not, and I'm still undecided what light to buy next or buy 3 more like I have.
 
I should have known it would get confusing.  Its LEDs, its always confusing.  I think I am going to replace some of the MH bulbs and swap the bad ballest with an LED set up, see how it works this winter and then rethink next winter.  If I wind up with all LEDS, I wasted a bit of money on bulbs but it is worth it to get the education.
 
Almost forgot: How much heat do they put off?  I vent my grow room out the dryer hook up, but not the office.  Thinking of putting LED in office so I can work with plants in the room.  Makes me feel good to see plants, not to sweat.
 
You can figure about 15 to 20% of the actual power draw is converted into heat. So its not that difficult to figure out how much heat they produce. A 250 watt led would put out about as much heat as a 50 watt incandescent light built, not counting the heating effect of the light produced.
 
Hafners said:
You can figure about 15 to 20% of the actual power draw is converted into heat. So its not that difficult to figure out how much heat they produce. A 250 watt led would put out about as much heat as a 50 watt incandescent light built, not counting the heating effect of the light produced.
 
Thank you.  That is manageable.

How about fan noise?  Would they be comfortable in lets say your living room?
 
 
I would say most aren't any louder than a computer tower. Most are cooled by 80 mm computer type fans, some actually use the quieter more efficient 120 mm. My little 45 watt is dead silent, it doesn't need a fan.
 
AJ Drew said:
I am old school metal halide / high pressure sodium.  Lost a ballast this past year and it is about time to replace bulbs all around.  So it would be a really good time for me to make the plunge into LEDs.  Problem being, there seems to be no standard in replacing lets say a 1000 watt HID light with LEDs.  Every LED manufacturer has its own way of rating and comparing.

Could folk dumb this down for me?  Tell me what you bought, how well it works, how much coverage it provides.  Even telling me what models you bought when you were disappointed with the results will help me figure this out.
 

1000 Watts? About 35W for LED will do. If you find one that is around 50W even better but I never seen a LED bulb over 35W. However, you can always, use Y-Splinters.

I use LED lights since years now and I am very pleased. Just try to get LEDs from "Good Quality Made in China" and above. Dirt-cheap LEDs from China should be bought at your own risk.

I use x5 15W bulbs (75W total) for videos and photography and the room in so illuminated that the rest of the house looks dark when your eyes get adjusted to the light. With that light, I can take photographs at ISO 100 and the camera works just slightly slower than when the flash is used. Photographs turn out great.

I can take some pictures for you if you wish.
 
Also, I wouldn't try to go with one big unit to replace a 1000 watt hid. I'd go with several smaller 130-250 watt actual draw units for better coverage and canopy penetration. And, while cob lights are all the rage right now, the panels with a buttload of smaller LEDs provide better penetration since they don't act like a point source of light, the cobs are just easier and cheaper to produce so they have a bigger profit margin. If you would go so far as to diy a light, then it's much easier to go with cobs, but then its better to use a bunch of smaller lower wattage bulbs for more even coverage.
 
Hafners, can you point me towards coverage guides?  Ideally, I would like to build table's that are the same width as the coverage of smaller bulbs.  That way I could easily move between them rather than the sea of green monster of a grow I do now.  Tables are on rollers, but getting to the back ones means moving bunches.  Trying not to waste light.  If the tables were the same width as the light coverage, I could hang white blasted at the ends and bounce it back.
 
MrCtChilihead - I much prefer MH and HPS too, but my electric bill is so high the wife wants me to build insulated grow room in the barn and install its own furnace cause it is on its own drop from the pole.  That way, if we ever get audited I can show that the barn is for the business and the electric usage is for real.  OH and that way the DEA will hopefully throw the flash bangs in the barn.
 
 
AJ Drew said:
  OH and that way the DEA will hopefully throw the flash bangs in the barn.
 
 
A high power bill isn't probable cause to search and enter anymore. A lawyer beat that a long time ago.
 
They need more than that to go on. Therefor that'll never happen to you.
 
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