Any electricians on fluther?

Asked by El_Cadejo (34610

) November 7th, 2008

Im trying to make an LED array for one of my fish tanks and had some questions about the power supply. I took an old laptop power supply and cut off the plug right before where it plugs into the “brick” well there were three wires so i didnt know how to figure out which was pos and neg but i got that all figured out now (funny story involving PnL, fire, and explosions) anyway my question now is, did that brick act as some sort of resistor? is there anyway to know,short of getting something to measure the voltage coming out of this(im poor right now). According to the “brick” its 12v but like i said, dont know if that limited the electricity coming out of the wall or not. Thanks

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7 Answers

http://www.fluther.com/users/chris6137/

Snoopy (5798

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The brick is dropping the voltage from 120 to 12v and it is also converting from AC to DC. If you removed the brick part you are getting 120AC and you would fuck up your LEDs.

jrpowell (40562

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@jp alright thanks, thats what i was thinking, i really didt make much sense why id have the fire and all if i was only getting 12v.

another question, im screwing around with a 9v battery and some LEDs, if i hook the positive lead up to the positive on the battery it powers on, which makes sense. Why does it also power on if i hook the positive lead up to the the negative one on the battery?

El_Cadejo (34610

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