I’m measuring a negative inductance. How is that possible?

It should be noted that at very high frequencies, the winding capacitance of a coil becomes dominant and the impedance decreases significantly again. In this range, inductance can no longer be reliably measured because the coil effectively behaves like a capacitor.

A dominant capacitance in the inductance range is displayed as negative, just as inductance in the capacitance range (when measuring a capacitor at very high frequency) appears negative. Ultimately, the LCR meter measures complex impedances and converts them to either C or L. The sign depends on whether the phase angle is greater or less than 0.

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