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I know that some multimeters measure capacitance by applying a constant current in a time Delta t, measuring the voltage difference before and after the current was applied, and solving

I = C * (Delta V) / (Delta t)

How do they measure an inductance?

Vladimir Vargas
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    reluctantly! ;) – Scott Seidman Feb 21 '17 at 20:48
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    There are hints in [this answer](http://electronics.stackexchange.com/a/94368/107479), although the question isn't exactly the same. – dim Feb 21 '17 at 20:50
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    http://www.wikihow.com/Measure-Inductance This link may help even though it usually requires some more circuitry to do so. – 12Lappie Feb 21 '17 at 21:10
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    @12Lappie I wonder why the squared root of 3 is used in the second method.. – mickkk Feb 21 '17 at 21:51
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    Some more sophisticated meters may have a small resonant LC tank circuit (like proper LC meters). The system measures the resonant frequency and the phase between the voltage and the current across the component under test, that way, it doesn't matter if you're testing a capacitor, inductor or resistor, as the meter can identify all three. having V & I in phase = resistor, while either a +90 or a -90 degree (I forget which is which) phase shift will tell you if you've got a capacitor or inductor and the change in resonant frequency tell's you it's value. – Sam Feb 21 '17 at 23:57
  • The question is pretty vague. Which multimeter (brand, model) do you know that measures capacitance with a constant current, and at what range and accuracy? Also, what is the purpose of your measurements? If you are working at MHz or GHz range, the DC value of a capacitor or inductance might be pretty useless. – Roland Aug 02 '21 at 13:30

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A multimeter I have clearly measures both capacitance and inductivity with a small AC signal (I'd guess in the order of 1kHz or so): measuring the inductance of a loudspeaker makes this quite audible.

Admittedly, it's not all that "multi": it doesn't measure voltages and currents but only passive components.

user139892
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  • would be nice to hear brand and model of your multimeter, and the range and accuracy for inductivity measurements – Roland Aug 02 '21 at 13:25