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Reefing it with LED's (help needed) Answered

Well this is my second post and I am a bit more learned in the ways of LED circuits from many of your posts.

Objective: Create a high light output LED array that will peak at around 16,000K for growing coral for reef aquariums.

Primary strategy: connect 10 or more Luxeon III stars in series

Preferred requirements: Energy efficient, Low Heat emittance, Needs to peak out at the appropriate spectrum for the coral ( I have that covered just by changing the ratio of cool whites to royal blue Luxeon III's)

At the moment I a just going for a simple on/off, later i would like to employ a form of automated dimming so that it fades on and off so there is not such a sharp on off with the LED's. So far I have a circuit that i plan on modeling my LED array after since it was readily available for me to dissect. The following is an LED array. I know that there is a diode rectifier bridge built in there and a smoothing capasitor but there are to components i do not recognize they are connected at the positive and negative ends of the circuit. One is the Yellow (doohickey with part # 684j 250) component attached to the positive lead and the other is a clear (fuse/resistor hybrid) component next to the resistor on the board.

I was able to draw the circuit and it seems pretty straight forward but I just need to know if I will be able to spec the appropriate components to operate 10 leds in series (Each LED operates with a Vf=3.9 V and I= 1000mA ) they will need a supply of more then 40V DC.

Any help or dialogue I can get the more the better and the more I will learn

In addition I looked at Dan's high power constant current but not sure how well it would operate under the conditions that I have specified

Primary LED's in use for the Reef light: (note all are stars)
LED part # Color Type Vf Amps Lux
LXHL-LW3C cool white Lambertian 3.9 1000mA 80lumens
LXHL-LR3C Royal blue Lambertian 3.9 1000mA 445mWLumens

LXHL-MW1D cool white " " 3.42 350 mA 45 Lumens
LXHL-MRRD Royal Blue "" "" 3.42 350 mA 220 mWLumens

There was little to no difference between the 700 mA series and the 1000mA series so I did not list them

I look forward to all your help


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13 years ago

look up for the driving high power led's instructable


13 years ago

Tom, The example LED circuit you show will not work for the high power LEDs you want to use. The yellow component is probably a high voltage AC capacitor. A switching current driver will work. Just do a internet search for "LED power driver kit". Try different combinations of these words and others. Mike