Calling out to Weezard for LED advice

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Originally Posted by mx4intx

Good enough is good enough for now. I can improve it later. Nice to hear from you Weezard. When I upgrade I'll probably have to bolt them down anyway since I'll want more light and it will mean a lot more heat. I am probably going to order one more blue LED for now since the PSU will support it. That makes 5 blue 460nm, 4 660nm, and 4 625nm. I figure it might help keep the plants a bit shorter anyway since most people advise a low dense grow with LEDs.

Peace

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Wow!
That's a metric shitload of high energy light.
That ratio will make for very squat gals.
Perhaps too squat, (depending on relative efficiency of the emitters). :)

I suggest that you put a dimmer in-line with the blue string so you can trim the B:R to control the amount of stretch suppression.
I'm jus' sayin', an adjustable ratio will give you fine control and 6 amp dimmers are not expensive.:cool:

Aloha,
Weeze

If you are talking about r2 on the adjust leg I have been wondering what exactly I would need to do that.

Right now I only have 4 of the blue and 8 of the red. I just fiigured why waste the volts.

Quote:

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Originally Posted by mx4intx

Good enough is good enough for now. I can improve it later. Nice to hear from you Weezard. When I upgrade I'll probably have to bolt them down anyway since I'll want more light and it will mean a lot more heat. I am probably going to order one more blue LED for now since the PSU will support it. That makes 5 blue 460nm, 4 660nm, and 4 625nm. I figure it might help keep the plants a bit shorter anyway since most people advise a low dense grow with LEDs.

Peace

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At your chosen ratio, assuming emitter efficiency of over 25%, you're looking at wanting to keep that panel way above your plants.

I got some needlessly dense growth during veg with similar ratios, you gotta keep the light higher during veg to allow for stretch and then slam it close for dense flowering.

The dimmer should take care of that I guess and after using that for a while I will know how much of what color to add more precisely.

Anyone have any thoughts on this circuit, supposed to run LEDs off AC. Sounds useful for big high powered LED arrays. I found the circuit he referred to first.

AC-LED

Quote:

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Originally Posted by mx4intx

The dimmer should take care of that I guess and after using that for a while I will know how much of what color to add more precisely.

Anyone have any thoughts on this circuit, supposed to run LEDs off AC. Sounds useful for big high powered LED arrays. I found the circuit he referred to first.

AC-LED

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10mA average from the bottom diagram, not useful for high powered arrays at all.

Quote:

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Originally Posted by mx4intx

If you are talking about r2 on the adjust leg I have been wondering what exactly I would need to do that.

Right now I only have 4 of the blue and 8 of the red. I just fiigured why waste the volts.

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Quite right!

The dimmers I mentioned were the DC, 6 ampere, units that I used for the big light.
But, if you think about it. . .

'spose you could use a pair of 2 ohm resistors in parallel and use, say a 100 ohm, 5W. rheostat in series with one of them.
That will give a range of 1 ohm to 1.96 ohm.
That would just about halve the current when at it's max.
Thanks for suggesting trimming R2.

I probably should have done that and saved a buck or two.
Ah well, live and learn.

Aloha,
Weeze

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Originally Posted by khyberkitsune

10mA average from the bottom diagram, not useful for high powered arrays at all.

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Thats because that circuit has 20ma led's. Would have to do the math and change out most of the components to drive bigger LEDs. It's being able to do it that intrigues me.

or 10ma, whatever

from that link "A larger capacitor will increase the current and a smaller one will reduce it."

Yea being able to do it is no problem. You must, absolutely must limit the reverse voltage though when powering straight from AC without a dedicated driver (just resistors and caps and a couple diodes.)

I dont think you understand the circuit.

heres another one

Circuit - AC Powered White LED Strings