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Old 01-20-2019, 01:27 PM   #47
Badpuppy
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Join Date: Dec 2017
Location: Guthrie, OK
Posts: 1,140
Default Re: 12 volt conversion

^^What katy said. And the resistance of a 12V bulb is 4x that of a 6V of the same wattage: W/V = A, V/A =R. From katy's example, 12/4 = 3; 6/8 = .75.

If you add a series resistor with a device with the same resistance (horn motor) the power dissipation is doubled, since the current must remain the same. The resistor dissipates the same power as the horn in heat, rather than honking.
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