12v current how to


Old 09-04-08, 09:52 PM
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12v current how to

I have 3 wires wire 1 is my light, wire 2 is 12v to power the light and wire 3 is another 12v to power the light but in pulses. So Im thinking i would wire #2 on #1 then something that will block power to come back through to wire #2, then wire #3. So when i activate wire #2 lite comes on, then when i activate wire #3 it overrides wire #2 and does the pulse. There are 2 lights and when i wired it up and activated wire #3 it made both lights pulse and that is my problem i dont want the current to go back through wire #2 to the other light. So basicly i have 1 12v contant to power both lights and 2 12v pulse. If this makes sense to anyone what would i do to solve this? I thought resistors only go forward if so what size to keep 12 through and through i dont want the volts to drop after it comes out the resistor.
Old 09-04-08, 10:38 PM
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A two filament automotive bulb might be a simpler solution. One filament continuous, one flashing. only problem may be one filament in that type is usually brighter. If you wanted equal brightness you could drop the voltage to the brighter one with a resistor.
Old 09-05-08, 05:11 AM
Join Date: Apr 2007
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Assuming this is DC voltage, put a diode on wire #2. A diode allows current to pass in one direction only. Make sure it is rated for the current it has to handle.

Or, use a relay to switch between wires 2 and 3.

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