In a message dated 3/22/05 2:00:14 PM Central Standard Time, TexasRF@aol.com
writes:
I lost track of who said what/when;
In a sine wave the average voltage is zero therefore average power is
zero.In an ac circuit with sine wave voltage, average current is also zero.
One
could be led to think that average power is also zero?
All power formulas square the voltage or current to get rid of those
negative terms.
The square of a positive number is a positive number.
The square of a negative number is a positive number.
The RMS value is the squareroot of the mean value all of those
instantaneous power measurements over some finite period of time.
The period of time over which the RMS value is measured can make a huge
difference in the answer.
The commonly known conversion factors only apply to pure sinewaves and
averaging over multiples of full cycles of the waveform.
As far as I am concerned, Peak measurements are the only way to go.
Regards,
Dennis O.
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