Pyle Power Capacitor, Pyle of what?

[AndrewT]

charge the 5F cap up through a 1A constant current source (one lm317 and one resistor).
The voltage across the 5F cap should rise at exactly 1V every 5seconds.
Similarly if it is discharged at 1A then the same rate of voltage change occurs -1V every 5seconds.

 

[pforeman]

parts express has the big guys on sale now for cheap.

I don't see any values for ripple,tolerence, lifetime or ESR.


Speaking of which,
Sometime I need to replace the 100 V 25000 guys in my Moscode 600.

If I put 5 of these 20V guys in series, the cost would be about the same as 2 caps from digikey (or elsewhere), and the value would be far higher.

I find a wide range of prices for the same value caps even from the same manufacturer (different electrolytic?)
What would be the value for ripple, ESR that I should look for,or should I just get 100 V. 25000 (or larger) caps and look for as long a life cap as I can find
Thanks
Paul

 

[metalsculptor]

@ pforeman, to compare components you need to get the manufacturers data sheet for the appropriate part number.
What make you think the capacitor in your amplifier is faulty? 25000uF 100V sounds like quite a modern capacitor, probably a large can with screw terminals. Usually these have a long life (several decades) if kept cool. I have an amplifier with 10000uF 100V capacitors 22 years old which still work fine.

As for putting capacitors in series, the ESL and ESR add and the capacitance divides so the ESR will be 5 times that of the individual capacitor and the capacitance will be one fifth.

 

[AndrewT]

If I put 5 of these 20V guys in series, the cost would be about the same as 2 caps from digikey (or elsewhere), and the value would be far higher.

NO !
series capacitors reduce the effective capacitance.
You would need 25 off 25V capacitors connected in series parallel to give the equivalent voltage rating and equivalent capacitance rating. You would also need balancing resistors across every capacitor to ensure more equal charging and more equal voltage on each capacitor.

capacitance will be one fifth

Yes.

Not advised that you ever connect capacitors in series until you understand what you intend to do and why it is needed.