# LED driver question



## Treasure chest (Apr 21, 2010)

I made a DIY LED light using this driver AC100-240V to 3A Constant Current Led Driver for HERO-LED 100W Led Emitter [HL-100WHPL-LD] - $75.00 : Led Strips Hero-ledstore.com and 12 Cree XP-G in serial connection. The light worked for 2 days and no longer lit. I tried to unplug and replug the power many times, at one time it came back for another day and died. I measured the voltage from the driver but there is no constant reading. I got 12 something volts in a blink and back to nothing. Do you guys think if the driver has been toasted?


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## effox (Apr 21, 2010)

I think you overloaded it with 12 crees. There's at least 3v's each aren't they? The driver can handle a maximum of 36 dc output, but I could be wrong.

Try removing one or two of the crees from the series and see if it makes any difference.


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## davefrombc (Apr 21, 2010)

It may be.. ..If I read the specs on those Cree LEDs right, 12 of those Cree LEDs in series would drop 34.8 to 38.4v, and to run full brightness, draw 4.2 amps . Your CC supply delivers a max of 36v and a constant current of up to 3 amps. It was being run overloaded and likely failed due to heat buildup in the components.


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## Treasure chest (Apr 21, 2010)

Thanks for the feedback. I tried again today with 10 and 6 bulbs configuration but could not get them to lit continually. Either very dim or nothing. I have concluded that the driver is toasted. I am planning to get 2 drivers this time each drives 6 bulbs. Any suggestions on which driver should I get?


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## davefrombc (Apr 21, 2010)

I made an error in my thinking .. The 12 LEDs in series would drop 34.8 to 38.4 volts, but the current would have to be limited to 1.5 amps (1500 ma) because that is the maximum current each LED can handle. I believe for driving 6 Cree XP-G LEDs in series you would need a supply delivering 36 volts and a constant current of maximum 1.5 amps. I hope someone with more experience wiring up LEDs in series circuits will chime in because I am not certain my math and theory is correct.


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## gouedi (Apr 25, 2010)

That is constant current driver, blinking is self protection, 
Xp g can not be driven over 1500ma ,xm l is the better choice. 
Connect 6-8 xml, then will draw around 80w, meaning 80%of your power supply.

Ps, the led is bright, but the cri is really low, Cree claims the XML is the best one, but only have 80 cri,(same cri value as the standard t5ho blub), the best solution is mixing the led with a cri 90 t5ho bulb, or two. For example the osram LUMILUX DE LUXE T5 HO
965, the 965 blub will bring out the color, led can output enough light to the deep if the tank and create mh light effect.


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## Treasure chest (Apr 21, 2010)

Thanks for the help here. The LED is actually a supplement light in my MH pendent. The fixture used to run 2x28w Square pin PC bulbs in addition to the MH bulb but PC bulbs don't last long and they are expensive to replace so I decided to replace it with LED for good. I choose XPG because I use the light over my fresh water planted tank. I have since ordered a Mean Well ELN-60-48D driver. I am still waiting for a dimmer controller to arrive. Will update on how it goes once I test it out.


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## Treasure chest (Apr 21, 2010)

I have another question here. I am trying to use a 9V power supply with potentiometer to dim ELN-60-48D. I measure 14 volts unloaded, but when I hook up to ELN-60-48D with potentiometer turned all the way, I only got 6+ volts. The driver supposed to be dimmed with 0-10V signal, my question is if the control voltage should be unloaded or loaded reading.


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