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Outlet to DC conversion

  1. Jul 17, 2008 #1
    So, I work in a lab and something we use is powered by 3 D-cell batteries (we just found out after they died after three years of use, and deciding to pull it apart). We want to maybe make this run on an outlet for increased consistency, but don't know if that's possible/a good idea. Any input on how to do this would be great!
  2. jcsd
  3. Jul 17, 2008 #2


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    Staff: Mentor

    Three alkaline cells give about 3 * 1.5V = 4.5V. You could replace them with a wall transformer style power supply, probably a 5V or 4.5V one. Check out your local Radio Shack store or equivalent.
  4. Jul 17, 2008 #3
    Cool, thanks, wasn't sure if it was as easy as that.
  5. Jul 17, 2008 #4
    1. If it operates three years on one set of batteries, why bother modifying it?
    2. A cheap wall-wart power supply will introduce a fair amount of ripple to the power section of your device. That can have detrimental effect on operation and reliability.
    3. Unregulated power supplies (many/most wall-warts are unregulated, or poorly regulated) may cause even more problems wit the operation of your device.
    4. Just to cover all the bases... wall-warts are notoriously inefficient. Considering the small power needs of your device, the transformer in the wall-wart will be wasting most of the power consumed.
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