Hello,
I am interested with the Self healing property of Metallized Polypropylene X2 capacitors.

Actuallay we'd a recent problem in some of our electronic boards which are using capacitive supplies and X2 capacitors as a current limiter. However, we'd faced with Zener diode problems in those boards which we use 2.2uF and 1.5uF X2 capacitors. Regarding to the current limiting mission of X2 capacitors, our main suspect in this failure is X2's because of its Self healing property. While Self healing is happening, X2 is short circuited for a small period and only the 33 ohm...

Re: Capacitor Lifetime Testing

Thank you arneson,
Here there is a bigger picture of your device.

[url]http://imagehost.vendio.com/bin/viewimage.x/00000000/powerlots/pyramidcra2a.jpg?vvid=65346282&allow_mailing_list=1&allow_track_link=1&track=02361b02e4-e19a4&sp=1[/url]

Also it is said to be 33$ here:
[url]http://cgi.ebay.com/Pyramid-CRA-2-Electronic-Capacitor-Resistor-Analyzer-NR_W0QQitemZ320041689958QQihZ011QQcategoryZ50962QQcmdZViewItem#ebayphotohosting[/url]

And also, looking its properties, it is not...

Re: Capacitor Lifetime Testing

Hi again Davmax,
Thanks for the schematics.
C1 and the inductor are used to prevent dc and ac voltages to pass accross the sources, is this true?
Also, as I see, most of the datasheets give the ripple current at 120Hz, not 100kHz, is this scheme directly convertable to 120Hz version?
With this rig is it possible to apply ripple currents in the range from 50mA to 3000mA or so while applying dc voltages from 10VDC to 450VDC?
Thank you very much,
Regards...

Re: Capacitor Lifetime Testing

Hi davmax,
Thank you very much.
Is it possible for you to send a basic schematic of the test circuit you suggest?
Will be very happy upon your help.
Thanks.

[SIZE=1]The request to make this cap setup is not too easy. It depends on the type of caps and their value.

Example. Some can take 3.2 amps (Samxon 3300u 6.3V). To add this level of current into 9 milliohm requires an rms voltage of only 28mV. This represents quite a small power of 90 milliwatts. So what is required to produce the 100Khz...

Hi you all.

I am trying to setup a suitable circuit that applies the desired max ripple current to a capacitor which also has the rated DC voltage accross it so that I could realize the lifetime test.

May anoybody help me what kind of circuit to use and the necessary formulas?

Thanks...