PSU with KME capacitors, recap or not?

[Y. Signal]

Hello, I have this PSU from 1994 using Chemi-con KME and Chemi-con W (custom?) capacitors and I'd like to know if it's better to recap or leave it as is. These are the capacitors used in this power supply:

• 1x 100 uF 10V Chemi-con KME
• 1x 120 uF 200V Chemi-con W
• 3x 330 uF 16V Chemi-con KME
• 3x 2200 uF 10V Chemi-con KME
• 1x 2200 uF 16V Chemi-con KME

Initially I've considered to recap using KMG, the indicated KME replacement, but some of them are very expensive to order here. Looking for another suitable replacement I've found that Rubycon PX have almost identical rated ripple current (some times just a bit more), but ESR is not indicated. For the Chemi-con W, since it seems to be the input filter, I've considered using Rubycon BXW or some similar capacitor rated 250V (or more if it fits?)

Since this circuit uses GP caps, does that mean that it's not very picky about ESR? if so, are the Rubycon PX or another GP caps with the same or a bit higher ripple current suitable?

Chemi-con KME datasheet
Chemi-con KME datasheet with max.ESR
Rubycon PX datasheet

[dmill89]

Re: PSU with KME capacitors, recap or not?

non-water based Chemi-Cons like these will probably last until the seals finally dry-out and shrink (which could be a long time I've got equipment from the 1970s with quality Japanese caps that are still good). Granted they are 24 years old and if replacing them certainly won't hurt anything (as long as you don't accidently damage something in the process), but it may not provide much benefit either. Unless you're experiencing issues or the equipment is in a critical application I probably wouldn't bother.

[Y. Signal]

Re: PSU with KME capacitors, recap or not?

Thanks, nice to know that KME are good. This PSU gets a bit hot since it's in a plastic case with not much ventilating holes, anyway I think I'll leave it with these capacitors meanwhile it works fine. The machine is mostly turned off and it's turned on for 1-2 hours from time to time.

Anyway, are my proposed replacement adequate? any other suggestion?

[momaka]

Re: PSU with KME capacitors, recap or not?

Anyway, are my proposed replacement adequate?

Yes, Rubycon PX is more or less directly equivalent to Chemicon KME/KMG, along with Nichicon VZ. I forgot what the Panasonic equivalent GP caps were. I think NHG?

Anyways, I agree with dmill89 - no need to replace these caps if there's no issue. I have amplifiers from the late 70's to the early 90's - all with original caps and still going strong.

[Y. Signal]

Re: PSU with KME capacitors, recap or not?

Thanks momaka. I'll leave them meanwhile the unit works fine, anyway it's nice to know what would be a suitable replacement.

I think so, NHG are GP 105ºC too: https://cdn.badcaps-static.com/pdfs/...bfd8d6ffc3.pdf