Power conversion

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Power conversion

Postby Stevers » Fri Aug 05, 2005 11:01 am

how do I convert 2.5 watts at 120 volts AC to ______watts at 12 volts DC

Postby Guest » Fri Aug 05, 2005 6:35 pm

If your converter/inverter were 100% efficient, it would still be 2.5 w. Some power is wasted in the conversion device, so expect more power going in the input side than comes out the output side. I can't suggest a factor, it will be device dependent.

The current however will scale (volts x amps = watts), so the dc current to produce 2.5 w at 12 V will be 10x the ac current at 120 V (again assuming 100% efficiency, 70-80% is probably more realistic.)

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