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Testing 3 Watt LED's Answered

I recently purchased 13- 3 watt LED's. I'm trying to establish a high out-put LED light.
I also purchased a LED Driver Transformer 48 Watt 120 Volt to 12v DC 4 Amp.

First I would like to test each LED using the same divider.

I'm thinking that if I create a voltage divider two 330 ohms to limit the current and reduce the voltage to about 6 volts that would allow me to test with the driver that I purchased.

Secondly, will this driver be enough to drive all my LED's and would I have to reduce the voltage down too since it appears to push out enough wattage and amperage for the total number LED's I'm putting together?

I'm building my circuit based on this video.


Link to website data of 3 Watt LED.

Assistance would be greatly appreciated.




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9 years ago

LED Spec

I did measure the voltage on the LED Driver. It is a DC power supply with a regulated 12 volts. The reason for the voltage divider is to reduce the voltage on a single LED to for testing purposes.

I do realize now that for all these LED's to work in series I need a bigger power source. I haven't figured out the right size though. I have an old PC that I can gut out for the 200 watt power supply and it's regulated, so that might work?