Think ive been led astray
- Thread starter leds420
- Start date
cdgmoney250
Well-Known Member
I think the LED section of RIU is dedicated to more than just DIY lamps... And I also believe that the OP started this thread referring specifically to SK yields and whether the lamp was worth the money or not. (Then they disappeared never answering even very simple questions about the grow space.... Hmmm)
alesh
Well-Known Member
This surely is what this thread is about. My point is that we'd be seeing 3+ g/W there if it were possible to get 2 g/W with top-bin XB-Ds (which SK use; they're about 28% efficient at 700mA and there are driver losses as well).
And no one is close to it.
The OP created the thread to setup for hard core sales push. create the controversy, and then under identities promo the lights.
testiclees
Well-Known Member
Ya OP has just a single post.
BobCajun
Well-Known Member
Your math is flawed. There is a limit to the g/w that can be obtained from Cannabis in a certain area. Beyond a certain point, about 1500PPFD, there is very little benefit to more PPFD, regardless of how your LEDs are driven. 18 inches directly below a 400w SK it's over 1700 PFD.
Stephenj37826
Well-Known Member
Actually you spread the light more. G/w is directly connected to efficiency. The more light you have per watt the more yield per watt
BobCajun
Well-Known Member
It's not limitless nor linear though. How many lumens per watt are the best DIYs producing? Most of the DIY light grows I've seen used 500-800 PPFD. Obviously, you're going to get average yields with that. Now if you were to cram a bunch of cobs into a fixture then you might get a higher yield. All I've seen is people trying to save on power consumption, not obtain high PPFD levels.
Last edited:
Stephenj37826
Well-Known Member
Over 220 and yes photons are photons. Say 100 watts at 30% is 30 par watts. 100 watts at 60% is 60 par watts so twice as much light. It's not limitless but 30% is far away from viable. So 400 watts of cxb3590 driven at 700ma at 64% will produce 2x as much as a SK at 400 watts at 30%. Just bottom line 2x the photons produces 2 times the yield all other things the same.
Last edited:
Growmau5
Well-Known Member
Gorilla marketing at its finest. If the OP is with SK, they must believe " any press is good press"
the OP joined Aug 19, 2015 and succeeded in creating one of the most active threads in the last 2 weeks. I think its really funny.
Nothing creates more butt hurt than a good ole SK thread, lol
Say what you will about SK but they serve the same special "kool-aid" that advanced nutrients did back in the day. once you drink it, nothing can convince you otherwise.
the OP joined Aug 19, 2015 and succeeded in creating one of the most active threads in the last 2 weeks. I think its really funny.
Nothing creates more butt hurt than a good ole SK thread, lol
Say what you will about SK but they serve the same special "kool-aid" that advanced nutrients did back in the day. once you drink it, nothing can convince you otherwise.
cdgmoney250
Well-Known Member
Maybe they were trying to use reverse psychology marketing... Tell you that you don't want one so much that you get one out of spite haha
Last edited:
Stephenj37826
Well-Known Member
PPFD isn't a measurement in a certain spot of a grow area. PPFD is the average par measurement over a given area. Yes SK has a hot spot dead center under the light. You can mount a screw in led bulb really close and get that to lol. What the whole grow area is covered in is what counts.
BobCajun
Well-Known Member
What you normally get with the 400w SK is about 650 grams, so about 1.44 g/w. Nothing wrong with that. That's about standard for LED grow lights, 1-1.5 g/w.
Stephenj37826
Well-Known Member
A
Are those numbers you've personally seen or was it in SK videos? I could write down any number on a chalkboard and say see how much we produced lol.
BobCajun
Well-Known Member
It was on the SK YouTube channel but it was legit. They weighed it up right there. There was an independent witness present. A great thing about them is that the power supply is dimmable by internal potentiometer which adjusts the output current between 50-100% of the normal current of 700ma. So you can just dial it down to get increased efficiency like with the DIYs. I saw the power supplies in their video where they did a tour of the manufacturing shop. They're Mean Well A type (I could see the A), with the two black spots on them, which I assume one of which gives access to adjust the potentiometer with a screwdriver. The type A has the internal potentiometer while the type B has the PWM kind of dimmer. It's lucky they use the type A. I don't really need to run them at full power for my small space so I want to dial it down to about 75% for a 3'x3'. That should yield a pound.
Last edited:
cdgmoney250
Well-Known Member
That is an incredibly presumptuous remark. Completely dependent on a list of variables almost too long to write down.
alesh
Well-Known Member
It's not
Twice the efficiency means that you can use half the power to provide the same amount of photons. And when you're using half the power, the g/W figure is obviously 2x higher.
Great news for DIYers as it's possible to build more than twice as efficient lamp as SK. And now you know what that means...
I think it's quite funny you are calling out alesh on his math! You obviously haven't read some of his other posts.
You don't have a good understanding of math when say there is a limit to grams/watt in a certain area. No one knows the limit of LED efficiency in the future. As the efficiency approaches 100%, the grams/watt approaches infinity. Area has absolutely nothing to do with grams/watt. You can say there is a limit to the grams/area but power usage is an independent variable.
So much misinformation from one person. MW Type B offer more flexibility than the type A models. They can be dimmed with an external potentiometer, PWM is not required but an option.
It's clear you got duped by SK and are coming on here beating your chest trying to justify your purchase to others on the forum. Please stop that as you might confuse others that are unaware.
BobCajun
Well-Known Member
But what if you don't have an external potentiometer? Obviously, an internal one is better because you don't have to buy an extra gizmo. I've read as much info about SK lights to be satisfied that they are a good product, though more costly than a DIY cob unit. But for a convenient out of the box grow light, the SK will serve my current purposes nicely. I don't like the bulkiness of it, but I can live with it. Later I'll do a DIY cob. Right now, just too much trouble ordering all the stuff and mucking around to assemble it. Later Ill just use the power supplies from the SK unit to drive cobs.
alesh
Well-Known Member
Thanks. But 100% efficient lamp doesn't mean infinite g/W. If the limit for 50% efficient one were 2g/W (or whatever), then 100% would achieved 4g/W.