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Current Limiting and Impedence

Original poster: "Mark Dunn" <mdunn@xxxxxxxxxxxx>


All:

Please follow my math and explain my confusion.

My TC power transformers have an impedence Z = 1.2 Ohms(secondary
shorted).

I built a Current Limiting Inductor(CLI) with L = 15 mH, thus at 60Hz
 X = 2*Pi*60*.015 = 5.65 Ohms. The R for the CLI is negligible. So the
inductor Z = 5.65 Ohms. The system therefore has total impedence of Z =
5.65 + 1.2 = 6.85 Ohms.

This limits current to 120 VAC/6.85 Ohms = 17.5 amps.
I have confirmed this through testing.

Measuring voltage BETWEEN the inductor and transformer I get around 90
to 100 volts(Mains 120V). So if I break down the circuit and consider
the current the individual components...
Transformer I = 90 VAC /1.2 ohms = 75 amps
CLI   I = 30 VAC /5.65 Ohms = 5.3 amps

Obviously, one can't analyze the components this way.  Is it because the
voltage measurements are not accurate due to the phase angle?  Am I not
allowed to analyze individual component impedence?  What don't I
understand.

Thanks.
Mark