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those have a nice thick base and should work ok. i would cap it tight to the top of the fins to force airflow between the fins as opposed to over top of them
 
CobKits said:
dimming one meanwell driver at a time = 100k pot
2 drivers at a time 50k pot
3 drivers = 33k
etc.
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Thanks, and sorry for all the questions. I just think they sold me the wrong caps or something. 100k pot drops my amps to a max of 700mA when turned all the way down an still shows 700 ohms resistance on the pot.
Doing the math I should only need around 40 ohms to cap my drivers output to 2.8A from 3.3A running 4 chips.
 
boilingoil said:
Thanks, and sorry for all the questions. I just think they sold me the wrong caps or something. 100k pot drops my amps to a max of 700mA when turned all the way down an still shows 700 ohms resistance on the pot.
Doing the math I should only need around 40 ohms to cap my drivers output to 2.8A from 3.3A running 4 chips.
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look at the datasheet it will tell you the exact % of dimming for a given resistance
 
TurkishRambo said:
Looks like 500m3 fan blow air good thru mine 90cm cooltube. So my point was to use only main fan without any 12v fans. Tube should look like this but with plastic top part:
IMG_1973_site.jpg
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Looks interesting, where do you get those?
 
Wath will be the umol/j if i run
1212 gen 5 at 5watts ?

10 umol /joule
Best efficiency !
That mean we need 4 time less watts achive same ppfd
40 1212 at 5 watts each will provide
2000 ppfd 200 watts ! And i dont think it will need heat sink .
 
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swedsteven said:
10.4 umol /watts
Best efficiency !
That mean we need 4 time less watts achive same ppfd
40 1212 at 5 watts each will provide
2080 ppfd in a 5' × 5'tent total of 200 watts ! And i dont think it will need heat sink .
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thats not accurate.

10.4 ppfd/W is arbitrary to my test and has no relationship whatsoever to your space. i have other tests in my sphere where the numbers are over 40 ppfd/W that doesnt mean there is 4X more light
 
Ok but can u tell me how much umol/ watts will it provide at 5watts a 1212 gen 5 3000k 90cri ?

ill be interest in building a setup that i could dimme 400watts to 200watts to have the best efficiency with 40 cob on to a 3' by 3' metal or aluminium board and a meanwhell 400?dimmeble
Even the driver and cob will last longueur if dimmed right?
 
swedsteven said:
Ok but can u tell me how much umol/ watts will it provide at 5watts a 1212 gen 5 3000k 90cri ?
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look up the old "cheap and cheerful" citizen thread, it had umol calcs for all the different spectrums. you can then use the chart above to estimate the relative umol/J based on those currents and your current. you can also use the citi calculator but thats in lumens not umols. either way you are guessing on temp effects
 
I will love to build a "cob board" that beat all those other board lol 200 watts at 2080 ppf @energystar

Less cfm outake needed to up temp and dehumidificator .
50 cob at 5 watts each dimmeable to 10 watts each to match qb
just ad to spread those 50 cob to make it even and keep them closer to canopy .
 
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Will it be possible to run 50 cob 1212 at 5watts each and be able to dimmed up to 10 watts each ?
if yes wich driver will match that .
And will it be logical to do that or pratical
 
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swedsteven said:
Ok but can u tell me how much umol/ watts will it provide at 5watts a 1212 gen 5 3000k 90cri ?

ill be interest in building a setup that i could dimme 400watts to 200watts to have the best efficiency with 40 cob on to a 3' by 3' metal or aluminium board and a meanwhell 400?dimmeble
Even the driver and cob will last longueur if dimmed right?
Click to expand...
Why not get some QB 132's no heatsink needed and put on frame.....? cost much better.....think your coverage is going to be better ?
 
Dave455 said:
Why not get some QB 132's no heatsink needed and put on frame.....? cost much better.....think your coverage is going to be better ?
Click to expand...

To reach the best efficacy ppfd/w
49cob on a 4' by 4' metal plate
no heat sink no frame
490 watts dimmeble to 245 watts
Ill be able to keep the cob at about 4 inch to 6 inch and get the best coverage and high umol at the canopy with low wattage just to build the best !
20180402_075030.jpg
 
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