1200watt meizhi in 2x4x5

Pistil Kid

Pistil Kid

Well-Known Member
Come on guys instead of arguing maybe framing the replies another way would be a lot more constructive and beneficial. Something along the lines of " The main problem with 550watt light would be heat if you can get rid of the heat or if heat was not a factor then a 550w led would not be overkill. You may need to take into consideration the height you set the light above your canopy. etc etc." From what I have read it will depend on the light source and the efficiency as to what the accepted ranges are. Given that the lights in question are not that efficient then it is reasonable to conclude that 550w / true wattage or 70w / per sq ft will be ok. Now I could be wrong and that is ok with me I welcome the chance to learn if anyone can point out error in my example and explain to me why I am wrong. As they say the person who thinks they know everything and has nothing left to learn is an idiot.
General guide Watts per square foot (wattage per sq ft WILL vary by light source):
Minimum wattage per sq ft.: 30w
Mid Range wattage per sq ft.: 50w
Optimal Range wattage per sq ft.: 50-80w
 
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GBAUTO

GBAUTO

Well-Known Member
HydoDan said:
Efficiency doesn't matter watts are watts and create the same amount of heat...
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Dan, if the light is able to create more photons from each watt of power consumed( ex.: 45% vs 55% efficiency) then less of each watt is left as heat. More light and less heat from each watt as efficiency(efficacy) increases.
 
Randomblame

Randomblame

Well-Known Member
GBAUTO said:
Dan, if the light is able to create more photons from each watt of power consumed( ex.: 45% vs 55% efficiency) then less of each watt is left as heat. More light and less heat from each watt as efficiency(efficacy) increases.
Click to expand...
Nope,
watts are watts!!!
There is only less energy direct converted into heat, but more light is generated. You benefit from LED because you need less watts to produce the same amount of light energy. So you only need ~700w LED to generate the light quantity of a 1000w HPS!

Light is also a form of heat because the energy is stored by the photons and is released when it hits anywhere on a surface.
Think about your car and how it feels when it stand hours in the sun! Only warmed up by light energy!
But you can take a certain influence!
White surfaces converts much less energy than dark or black surfaces, so you get the lowest temperatures in white coated rooms!
Pure flat white can reflect up to 95-98% of the light energy, which increases the probability that a photon will anytimes hit one of the leafs.
 
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PSUAGRO.

PSUAGRO.

Well-Known Member
That's some height restriction, I would go with QBs or BARE cobs , dimmable drivers/setup ideally. 12/12 from seed with indica doms to make it somewhat manageable.

Also agree that +600w of efficient leds is overkill for that space, but it's your grow do what you want...........don't cry about the heat load later:)

flat white paint getting over 95% is hard to believe, unless it's almost pure titanium dioxide

good luck
 
Pistil Kid

Pistil Kid

Well-Known Member
Well I think we can agree if it is 600watts of cobs then it is overkill but 550w of the led lights you quoted then you will be alright.... cheers
PS If getting an answer to a simple question is that hard then I would hate to ask something technical or worthy of an intellects advice. It is no wonder people are leaving and taking their advice elsewhere. I am just new here and I can already see the decay in the forum. There are some really cool people here but ..... for how long is the question I would not blame them if they left. Answer positively and contribute or don't say anything, the internet is too large. People will not stick around to be subjected to attitude. Keep it real people .. peace my brothers.
 
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A

Antbash

New Member
PSUAGRO. said:
That's some height restriction, I would go with QBs or BARE cobs , dimmable drivers/setup ideally. 12/12 from seed with indica doms to make it somewhat manageable.

Also agree that +600w of efficient leds is overkill for that space, but it's your grow do what you want...........don't cry about the heat load later:)

flat white paint getting over 95% is hard to believe, unless it's almost pure titanium dioxide

good luck
Click to expand...
I'm just running the 300watt, I was just gonna buy another 300watt and run 2. Haven't even bought the 1200watt. Been hearing alot about cobs. Seems pretty challenging and pricy to build your own cob setup, but I really want to. Is the quality of light really like no other?
 
D

doz

Well-Known Member
Randomblame said:
Nope,
watts are watts!!!
There is only less energy direct converted into heat, but more light is generated. You benefit from LED because you need less watts to produce the same amount of light energy. So you only need ~700w LED to generate the light quantity of a 1000w HPS!

Light is also a form of heat because the energy is stored by the photons and is released when it hits anywhere on a surface.
Think about your car and how it feels when it stand hours in the sun! Only warmed up by light energy!
But you can take a certain influence!
White surfaces converts much less energy than dark or black surfaces, so you get the lowest temperatures in white coated rooms!
Pure flat white can reflect up to 95-98% of the light energy, which increases the probability that a photon will anytimes hit one of the leafs.
Click to expand...
You are right, but HydroDan is claiming that the efficiency level does not matter which is complete bullshit. You only get to utilize less wattage due to the efficiency. If you have 30% efficient LED from cheap panel vs. 60% efficient COBS, you need half the wattage to obtain the same usable output.

If OP has actual watt from a 25-30% cheap chinese panel, it would only be as good as some COBS driven at 50%. Even still it is overkill for a 2x4.

Maybe HydoDan was misunderstood and only meant that watts = watts (and including efficiency into his comment confused people). 400w of power is 400w with the same amount of heat output. You can have 400w of 60% efficient LED and 400w of 30% efficient LED and the heat output will be the same. The only difference is you have half the output in the 30% efficient as the 60% efficient light. The whole point to efficiency is lowering your power bill and heat output while getting the same amount of light.
 
PSUAGRO.

PSUAGRO.

Well-Known Member
Antbash said:
I'm just running the 300watt, I was just gonna buy another 300watt and run 2. Haven't even bought the 1200watt. Been hearing alot about cobs. Seems pretty challenging and pricy to build your own cob setup, but I really want to. Is the quality of light really like no other?
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ahhh , meizhi is a brand, didn't put it together..........I looked at it, don't waste a dollar more on that junk. A t8 fixture is more efficient than that mass produced chinese led "grow" light. Questionable/cheap diodes are being used (efficiency in the teens, bad thermal management, shitty plastic drivers,etc.). Do yourself a favor and save up for efficient cob or QB kits. It's not a challenging build with a couple youtube videos=== Definitely no reflectors or lenses on the cobs if driven higher than 700ma with no dimming option & a 5ft ceiling

use the "300w" fixture for veg,clones, mothers,etc..........or orchids,lol
 
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leoshitz

Well-Known Member
Go with a quantum board. Don't fall for box lights with cool names and cool paint jobs. That technology is two advancements behind. Ten years ago that would be a good light.
 
REALSTYLES

REALSTYLES

Well-Known Member
Randomblame said:
Meeehhh, sh*t!
Your aloevera is bigger than mine... Lol!:clap:
Healthy looking garden ...
... and your dog actually seems to consider which one he is taking as next, hehe..
Click to expand...
His fucking ass just knock over my Platinum Cookie but it's ok but I had to put the soil that spilled out lol
 
Rahz

Rahz

Well-Known Member
Antbash said:
What the title says. I want to run a 1200watt in my 2x4 hung in the middle at its highest point. Would it be great or you think a little overkill
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There's no way to tell for sure but my experience with blurple lights from China is that they run in the 20-25% efficiency range. That 550 watts might provide 110-140 PAR watts. In a 2x4' tent that works out to 14-17 PAR watts per foot. It won't be weak but nowhere close to overkill.

If you can manage the heat you should be pretty happy with the results, but it's not a good a deal as the advertising might lead you to believe. Spend 300 and DIY a cob lamp. You will get a bit more light, a lot less heat, and it will be running for years.

Or you could buy two of my T22s, would give you 25 PAR watts per foot (getting close to overkill) and only uses 400w at max brightness. :D
 
A

Antbash

New Member
Those QB are legit. Definetly buying one soon. For the mean time i added this apollo 250watt cfl with reflective hood that I totally forgot I had. Thanks for the help guys
 
Growerbert

Growerbert

Member
As far as I know, at least 32W true power is needed, for 1 ft².
MEIZHI LED 1200W, power draw is about 560W
560/32=17.5ft²
560/80=.7 ft²
Your growing area is about: 2*4=8ft²
You see, your plants will run well under this MEIZHI LED grow light loool
Plus, the price is friendly loool8)
 
GBAUTO

GBAUTO

Well-Known Member
Randomblame said:
Nope,
watts are watts!!!
There is only less energy direct converted into heat, but more light is generated. You benefit from LED because you need less watts to produce the same amount of light energy. So you only need ~700w LED to generate the light quantity of a 1000w HPS!

Light is also a form of heat because the energy is stored by the photons and is released when it hits anywhere on a surface.
Think about your car and how it feels when it stand hours in the sun! Only warmed up by light energy!
But you can take a certain influence!
White surfaces converts much less energy than dark or black surfaces, so you get the lowest temperatures in white coated rooms!
Pure flat white can reflect up to 95-98% of the light energy, which increases the probability that a photon will anytimes hit one of the leafs.
Click to expand...
You're making the assumption that ALL of the energy is being converted to heat-that isn't true. Photosynthesis gets its energy for the chemical reaction from light. The energy that the plant uses for photosynthesis isn't turned into heat-it's turned into plant. The net total energy may be the same but the energy that is being transferred into the environment isn't-at least until you burn the plant...
 
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