General > General Technical Chat
old electronic devices electrolytic capacitors
classicsamus87:
What is the manufacturers' website for me to clarify doubts about storing old electronic devices that have electrolytic capacitors for a long time but that the electrolytic capacitors do not have depolarization and defects?
my friend told me to use 1x per month for 30 minutes otherwise the electrolytic capacitors of the old electronics will depolarize and present problems
Gyro:
Most manufacturers's datasheets specify a storage life, but in practice, it isn't very useful for capacitors that have been in use for some time.
The following thread covers this exact question - hopefully it isn't the same friend. :)
https://www.eevblog.com/forum/beginners/doubts-about-electrolytic-capacitor/
classicsamus87:
I'm confused because some people say to use it every month, others once a year, other people say every 2 years to turn on the old electronics that have electrolytic capacitors but I need a solid response from the manufacturers but I don't have contact with them
Siwastaja:
"use every month" is obvious and total bullshit, completely ridiculous.
The problem is, you are not going to get very good and exact data from the manufacturers on this. It will be mostly anecdotal which I think you'll hate to hear.
Capacitor manufacturers leave this thing for the product designers to figure out, and the product designers then tend to ignore the problem and leave it to the end users unhandled.
Personally, I think the problem is way exaggerated by some. I have seen many elcaps die when overstressed by excessive ripple currents in hot environment, i.e. die in usage, but I have never seen an elcap die after powering up after long storage period. (I don't say it doesn't happen, just I have never seen it.)
mag_therm:
The first check is that the actual capacitance is in spec. That can be done by using a power supply to bias it, then making an R_C low pass filter and feeding that with audio gen.
Then:
You might be able to find functions for the DC leakage on one of the major manufacturer's data sheet for similar values and types to your old ones in question.
For example one function I obtained was I_Leak [uAmp] =3* sqrt(C) * V : C in uF ( I think Nichicon High ripple versions)
Then power up the old capacitor on a DC supply and take it up to say 80% of its rated voltage over a day.
Measure the leakage current. it may drop down over 24 hours or so. ( measure by discharge time with a stopwatch)
When stabilized, compare the leakage to the function for a new one.
On the old ones, 40 years old I tested like that, all the caps that did not have visual evidence of fluid escaping the seals,
had lower leakage than the function. I re-used some of them.
Navigation
[0] Message Index
[#] Next page
Go to full version