How to measure C-Coils

This is a brief guide on measuing C-Coils from Jantzen, as they cannot be measured as simply as other inductor types. 

"As mentioned in our website, you cannot measure C-Coils, like you would measure normal induction coils.

First of all you need a professional LCR meter or CLIO, measuring at 1 volt 1 kHz.

Secondly you cannot measure the coil on its own, because even with a professional LCR meter / CLIO you cannot measure the C-Coils correctly on their own, because the resistance is so extremely low on the C-Coils

Both LCR meters and CLIO systems will measure wrong when it comes to the inductance of the coil, unless you use the special measuring method no.2, as mentioned in this article:

http://daycounter.com/Articles/How-To-Measure-Inductance.phtml

The measuring setup will look something like the top image.

A precision capacitor (i.e. Jantzen 1% tolerance Silver Z-Caps) is connected in parallel to the coil and a resistor in series connection (values are not important).

If you use CLIO to measure it has to be set to 48 kHz sampling frequency and be rigged to impedance measuring (sinus function).

Then you do the impedance measurement, i.e. 100-5000 Hz, depending on the capacitors value (in this example a 5.6 uF was used).

You measure i.e 1.278 kHz resonance point and then insert them in the calculation schematic from the link above.

If all steps have been done correctly, you will then get an inductance measurement within the 5% inductance tolerance on C-Coils."