stockpot inductance and resistance

[nalawade]

I have a Stock pot made up of stainless steel.
I want to use it as a load on an induction cooktop.
I waned to measure the inductance of the stockpot. It is cylindrical

Image of the object whose resistance and inductance is to be measured https://i59.tinypic.com/4t62s9.jpg

Please advice

 

[chuckey]

Because your pot has no terminals , there is nowhere between which you can measure inductance. If you sit it down on your exciting inductance, the air gap between the two will have a massive effect. Just build a test jig and see what the effect is on the exciting inductance.
Frank

 

[nalawade]

Okay. There is going to be a litz wire through which I am going to pass the alternating current. This will induce currents in the stockpot (Load).

It appears like a transformer with Litz wire having N turns and Stockpot having 1 Turn only with leakage inductance.

The Litz wire and Stockpot together are considered as Inductance and Resistance in series which is my load.

As u said I want to calculate the total inductance and Resistance using a Test Circuit. But How do I build that Test Circuit ?

 

[BradtheRad]

The inductance (if it is what can be called inductance in the electronics nomenclature) could be present, although in a form that is difficult to measure.

The current is eddy currents in the metal. There is some resistance, although it is small. The voltage is small.

It is AC voltage, induced by the AC flux field.

The frequency of the AC flux field may make a difference as to the heating effect.

This is where an inductance parameter might enter in.

For a test, try clipping leads to opposite ends of the pot. Send various AC frequencies through it. High frequency, low frequency. See what impedance the pot offers. See if the data yields a curve, which would indicate inductive behavior.

It's a crude experiment, and it may not tell you much. However it may lead to some insight as to what experiment to devise in order to gain more information.

 

[chuckey]

Get hold of or build a flat coil, measure its inductance, sit your pot on it and re-measure the test coils inductance and especially its Q or equivalent series resistance.
An alternative way is to put a small capacitor across the coils (100 PF?), feed a signal generator into the coil with a series resistor (1K?). measure the voltage at the junction of the 1K and the tuned circuits. Adjust the frequency until the voltage is a maximum, this is the resonant frequency. measure the two frequencies where the voltage falls to .7 of the maximum, one high , one low from the centre frequency. The centre frequency divided by ( Fhigh- Flow), is the Q. You can calculate what the actual Q is by subtracting the effect of the 1K loading.
Frank