power measurements - RF Cafe Forums

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controlman

Post subject: power measurements

Posted: Fri May 07, 2004 6:26 am

Lieutenant

Joined: Fri May 07, 2004 6:22 am
Posts: 2
Location: UK

Hi everyone!
I found your notes on the internet very
useful. I was wondering if I may ask a small
question regarding the calculation of real
power dissipation from a simple R & L
components circuit connected in series and
powered by a an AC square wave. The
measurements I have is:

Power supply DC Voltage :V_dc
Power supply DC current :I_dc
RMS current through the circuit :I_rms

I simply wanted to know, why is the "real power " equal to V_dc*I_dc and
not V_dc*I_rms?

Thank you very much for your time and guidance.

Cheers,
Osman :?:

guest

Post subject:

Posted: Sat May 08, 2004 1:02 am

ask the king.

K5DVW

Post subject:

Posted: Mon May 10, 2004 3:49 pm

It seems to me that you havent given enough information about what you're looking to measure.

What do you mean by "real power"? The "Real Power" is the RMS power, that's how much work or heat to expect. Are you perhaps trying to find peak power? If so, that's simply Vpk*Ipk, where Vpk is the peak voltage of the square wave. There are some formulae to extract RMS power from a square wave if you know Vpk, Ipk and duty cycle.

Posted 11/12/2012

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