Problems measuring the average power with Picoscope

Forum for discussing PicoScope version 6 (non-automotive version)
ginger
Newbie
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Joined: Tue Apr 29, 2014 7:57 am

Problems measuring the average power with Picoscope

Hi there,

I´m trying to measure the average power on the secondary site of an power Transformator using Picoscope.

This is a Picture of my measurement:

The voltage V(t) is displayed as blue graph, the electrical current I(t) is displayed as red graph.
I´m using an advanced Trigger, so that the there is no jitter.
I´m also using a time ruler to measure only two periods of my signal.
I´m using a "Math Channel" to calculate the "Instantaneous power", a simply Multiplication of V(t) and I(t), which is displayed as green graph.

So far I didnt have any Problems, but now as I want to measure the average power, I have some Problems.

I do now want to measure the average Power.
The average power is easy to calculate, it is the integral of the instantaneous power over the desired period of time.
I´m using a new math channel for the average power, using the formula " 10500*integral(V(t)*I(t)) ". The factor 10500 is correct. So far, so good.
Now I´m adding an measurement. I do select the math channel "average power", I do select the section of the graph between the rulers (in this case two periods of my signal). But I´m not certain which type of measurment I should choose.
I did measure "Maximum", "AC RMS", "True-RMS" and "DC Average" in four measurements (as you can see in the Picture). But now I completly unsure which of this measurments does tell me my average power.

I´m pretty confused, because acutally I just want to know the solution of my integral, it´s a simple mathematical Operation. But I have to choose a "type of measurement" and I´m not sure which Option I should choose, the Programm is a Kind of black box for me at this Point.

Kind Regards

Jeff