EEVblog Electronics Community Forum

Electronics => Beginners => Topic started by: Adrian_Arg. on June 04, 2020, 03:28:59 pm

Title: Measure ESR with oscilloscope
Post by: Adrian_Arg. on June 04, 2020, 03:28:59 pm

Hello friends, I am trying to measure the ESR of the capacitors, using a generator FY6900 and Rigol DS1054z, and the method that it uses is the one of the video that is in the link, that and similar bulls, I cannot reach approximate measurements taking as a witness an ESR meter.
https://www.youtube.com/watch?v=115erzCCxgE (https://www.youtube.com/watch?v=115erzCCxgE)

in spanish
Hola amigos, estoy tratando de medir el ESR de los capacitores, usando un generador FY6900 y Rigol DS1054z, y el metodo que usa es el del video que esta en el link, ese y toros parecidos, no puedo llegar a mediciones aproximadas tomando como testigo un medidor de ESR.
https://www.youtube.com/watch?v=115erzCCxgE (https://www.youtube.com/watch?v=115erzCCxgE)

Title: Re: Measure ESR with oscilloscope
Post by: Vovk_Z on June 04, 2020, 03:58:03 pm

The result always depends on measuring method. That's normal. The problem is only if a difference is very large - more than 50-100%, for example.

Title: Re: Measure ESR with oscilloscope
Post by: rstofer on June 04, 2020, 04:23:25 pm

I think you are going to have to provide a lot more detail.  It's pretty clear that w2aew's method will work but there are a couple of issues:  Is the square wave coming from the FG between 0V and 1V?  The waveform can not reverse below 0V (a symmetric waveform from -0.5 .. 0.5 will not work).  What size capacitor?  The FG frequency depends on the capacitance since the calculated Xc wants to be very close to 0 Ohms.  For a 220 ufd capacitor, the author uses 200 kHz and Xc should be 3.6 milliohms.