Measure Inductor

Thread Starter

Romie77

Joined Jan 4, 2020
34
I want to measure an inductor of value 2.2uH but I dont have LCR meter.

Is there any way to measure inductor using function generator & oscilloscope?
 

dendad

Joined Feb 20, 2016
3,781
Add a known capacitor across it, and feed the sig gen to it via a 1K resistor, another resistor to the scope.
Tune the sig gen for a peak in signal level, then calculate the inductance from the cap value and resonate frequency.
You say you have a 2.2uH inductor, so, if you know the inductance, why are you trying to measure it?
Or, are you trying to make one?
Also, there are tables that allow you to wind inductors knowing the former diameter, winding length, wire size and number of turns.
 

Thread Starter

Romie77

Joined Jan 4, 2020
34
Yes I was trying to make it by winding wire.
I also tried to feed frequency to parallel L & C. But output was just decrease in amplitude of freqency.
Can you provide diagram and formula?
 

dendad

Joined Feb 20, 2016
3,781

upand_at_them

Joined May 15, 2010
759
I've done it this way with good results:

Connect inductor and good quality capacitor (10% or better) in parallel. Apply a 9V battery briefly across the LC tank and record the ringing on the oscilloscope. You should be able to get a nice sine wave that you can measure the frequency of.
 

upand_at_them

Joined May 15, 2010
759
Here, I did a screenshot for you. This is a 2.2uH inductor in parallel with a 1nF poly film cap. Signal generator is set to 6kHz square wave and the scope triggers off that, using channel 2.

Tank ringing is 3.47MHz, which results in an L value of 2.1uH.

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