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Need help wiring a solar panel to electric motor

  1. Apr 1, 2010 #1
    Hi everyone,
    i want to make sure that when i wire this all up im not going to start a fire :)

    So, i've got a 4W 12V solar panel the unit produces up to 333mA
    a 12V battery and a 12V DC 15 RPM High Torque Gear Box Electric Motor.

    I'm a newbie so don't much about electronics. All i want is for the motor to run and not blow me up.
    Can someone please walk me though what needs to be done, or what i need to buy if what ive got is wrong.

    Thanks in advance
  2. jcsd
  3. Apr 2, 2010 #2


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    I guess that, to be on the safe side, you should put a 1A fuse on the lead to the battery, right next to the battery terminal. The solar panel won't be capable of "blowing up" anything but a car battery can supply hundreds of Amps into a short circuit, if one should occur and could melt any leads and start a fire. A low value fuse will take care of that risk.
  4. Apr 4, 2010 #3
    A few things would be important here. I agree with sophiecentaur that a fuse is very important. But more than that, get a Schottky diode for the solar panel (schottky because of low voltage drop). I don't know what kind you have. It may have one built into it. But be sure. You don't want the battery to back-feed into the panel. It will burn it up if you're not careful.

    Also, a lot of this depends on how you're hooking it up. If you have a solar panel with a diode in series then the battery in parallel with a fuse in series (and a switch hopefully) and then the motor, you should be fine. It may be wise to post a schematic of what you're doing if possible. Panels can get expensive, so you don't want to blow a bunch up.

    Justin Coulston
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