Quote from: tinman on April 29, 2017, 10:00:54 PM
Yes
Unfortunately Russ got it wrong,as he was measuring a voltage drop across two resistor's,in which case power factor and phase relationship plays no part in calculating power dissipated by the two resistors.
Ohms law holds,and both the current through,and power dissipated by the resistors,is calculated using ohms law.

Phase relationship and power factor only come into play,when the inductors are included.


Brad

Yep. I cringe when I see some people misusing all that great test equipment and making the wrong interpretations of data due to their incorrect assumptions. Within purely dissipative elements like "ideal" resistors, you don't even need to consider phase between voltage and current at all, the power dissipated can be simply calculated by P=I²R or equivalently P=V²/R just using the RMS values of voltage drop OR current.

However for exactness one should include some small inductance in the "model" of resistors, as the wiring between components, the wire of the scope probe's reference lead, and the "real" resistors themselves always include some inductance. But in the present case these small inductances have only little effect on the outcome.

What _does_ affect the outcome in this case is the fact that the coil is acting like a Transmission Line, with distributed inductance and capacitance, that result in nodes and peaks of standing waves and reinforcement and nulling due to reflections along the coil.

Quote from: TinselKoala on April 29, 2017, 10:09:58 PM
That's a "sirius" problem all right, because your 220 VAC is the RMS value, and you should be able to charge your capacitor to very near the Peak value of the AC supply which would be about 310 V.

Yes
Sirius 

Quote from: padova on April 29, 2017, 10:03:42 PM
I wasn't get it right away. Somehow I assumed it was a positive signal from the FG, but obviously it was AC current,
so it was apparent power . Sometimes it is easy to fall into some traps.

Thanks to tinman  for experiment, it points to some directions.

It is important to realize that results of this kind can be obtained with totally positive signals, square pulses or sine waves with  even 120 percent positive offset (or negative offset), and in any inductive coil, whether flat Tesla Bifilar winding or round solenoid single-winding, as long as the stimulation is of such frequency so as to be able to see the Transmission Line characteristics of the coil. Of course it helps immensely if the coil in question has a lot of distributed capacitance along with its distributed inductance, and it is here that the Tesla Bifilar winding (whether flat or solenoid) makes the difference, by making these phenomena easy to see with ordinary equipment and ordinary lab techniques.

My response video to Russ's response video.


https://www.youtube.com/watch?v=nHqs72bYyUw

By using a TBF coil with more turns he could have brought the frequency range of interest down to within the range of his current probes. And as we know, as I have demonstrated,  you don't need a pancake coil to show the effect, it works just fine with TBF solenoid coils too, which are _much_ easier to wind. And it even works with monofilar coils, but less strongly since they have less distributed capacitance.

Russ demonstrated the phase shift which we all know is there and which will occur in _any_ inductive coil whether flat, solenoidal, Tesla bifilar, or monofilar wound.
It's too bad he didn't also demonstrate the power analysis software of his scope. He probably needed the current probes active and deskewed to be able to do that.

So the appropriate way to test this circuit is to measure the Vdrop across each resistor separately, without making groundloops by misconnecting the voltage probe references. In fact I do this using the same scope channel and probe, by moving the probe from resistor to resistor, so as to be absolutely sure not to introduce ground loops (and also I know for a fact that my FG's outputs are isolated from ground; is Russ's FG also isolated in this way? Many aren't.) This will give the actual power dissipated in the resistors, and no correction for phase need be applied in this purely resistive case.  Then one measures the power relationships in the inductive portions separately, and using the Phase Shift between voltage and current in the inductors themselves, one can calculate the Real power, Reactive Power, and Apparent Power in those mostly non-dissipative inductors. Here is where Russ's Power Analysis software in his scope would come in handy.