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12 Volt DC Connected to 120 Volt AC

  1. Mar 2, 2014 #1
    12 volts DC will travel thru a Diode connected to 120 volt AC , but will it put any load on the battery?


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  3. Mar 2, 2014 #2


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    Well, when the AC voltage drops below 12v and then goes into the negative part of its cycle, it will pull current out of the battery, theoretically an infinite amount assuming ideal sources, thereby causing the battery to explode. Don't try this at home, kids !
  4. Mar 2, 2014 #3


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    This is not a good idea. During the negative cycle of the AC (the + and- are reversed) and current will flow from the + of the battery through the diode- in fact, as soon as the AC terminal voltage drops below +11.4 volts or so and the current will eventually be so high that it will knacker the battery, melt the wires , blow a fuse.
    Don't touch mains voltages or big batteries until you can answer this sort of question yourself, without asking anyone. Be safe.
  5. Mar 2, 2014 #4
    One switch and two relays should work as the yellow line should carry 12 volts when power is off and carry 120 volts when switch on?


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  6. Mar 2, 2014 #5


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    Staff: Mentor

    Wow, crazy dangerous. Thread is closed.
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