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Q & A: battery-powered LED’s

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Most recent answer: 10/22/2007
Q:
I have a strand of LED lights that need 12 volts to push the color lights and 15 volts to push an all white strand. I have no knowlodge of how electricity works. How can I run these lights using regular battries? These lights are my portable samples so I need something small. These lights can run off 12 volts 24/7 and use 1/4 volt a month (so Im told) Help.......
- Art (age 46)
Waco Tx
A:
Sure, you can run LEDs off ordinary batteries. It sounds like 8 standard 1.5 V batteries in series (end-to-end) will work for one set, and 10 for the other.

How long will the batteries last? My memory of LED's is that a typical one fairly brightly lit will draw (very roughly) about 0.01 Amp of current. If that's right, then each battery will supply about 0.015 W of power. That's a lot less than a battery supplies in a regular flashlight. My guess is that even with AA batteries, you should be able to run for days. If you need longer between battery changes, and if you have room, you could switch to C or D batteries.
I have no idea what "use 1/4 volt a month" means. Maybe it was some other unit?

mike w

(published on 10/22/2007)

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