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Old 11-01-2011, 09:00 PM   #20
Jim/GA
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Default Re: 6 Volts versus 12

Quote:
Originally Posted by Jerry Parr WI View Post
Heat is a function of watts not voltage. When you halve the current but double the voltage the watts or heat stays the same. You can reduce the wire size but then you increase the resistance cancelling the gain. The savings in a 12 volt car is in the reduced cost of the wire.
You are correct, when looking at the load (bulb being lit, horn being blown, etc.).

The heat that I refer to is generated by the resistance found inside the switch contacts or the slightly corroded connector. The power (heat) generated there is I-squared times R. Half the current (at 12 volts) generates 1/4th the heat -- in the switch or connection.

See http://www.electronics-tutorials.com...resistance.htm

I agree with you that you can use a smaller diameter wire, too, if you want to.
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