Capacitors

[Chuck(G)]

I've been revisiting a lot of old power supplies and find that many of them have electrolytic capacitors that have gone south. The latest was a Senstron AT power supply--a very nice unit, but all of the filter caps on the output had popped their vents and were basically dry cans.

So, I'm wondering what folks would recommend for laying in a stock of replacements. I've used Nichicons and Elnas up to this point, although I do have a far stock of Spragues.

I'm thinking 220, 470, 1000, 2200 and 3300 uF, in 16 and 35 WVDC; maybe 15-20 of each.

What do you all recommend?

 

[Unknown_K]

Slightly off topic, but how much do those PS capacitors run and if you replace all of them is it economical compared to new $17 supplies at geeks.com?

I was going to fix a few 450W supplies for my older systems but new ones seem to be more cost effective so I junked the older ones. I can see fixing vintage supplies but it is hard to justify ATX era ones if all the caps need replaced (and who knows what else).

 

[Chuck(G)]

It depends on what your time is worth. I've seen ATX PSUs at Cascade Surplus for $5 the each. With that price level, there's no way I'd bother.

But getting decent older PSUs is getting less easy and the Senstron one that I just worked on is a beast. Three PCBs, monster inductors and quarter-inch thick heatsinks. German-made fan. This is what the hi-rel industrial folks use. Senstron still exists as an acquisition of Antron Technologies.

Not vintage, but still relevant to the topic, I see lots of LCD monitors that are junked because they "come on for only a few seconds". Those are no-brainers and idenifying the bad caps is easy. Same goes for routers--I picked up an Actiontec MI242WR FIOS unit that looked to be bricked--the power light didn't come on at all and the JTAG input was dead. Replaced the bulging caps with fresh ones and the thing came right up and has been happy ever since.

 

[Unknown_K]

It depends on what your time is worth. I've seen ATX PSUs at Cascade Surplus for $5 the each. With that price level, there's no way I'd bother.

But getting decent older PSUs is getting less easy and the Senstron one that I just worked on is a beast. Three PCBs, monster inductors and quarter-inch thick heatsinks. German-made fan. This is what the hi-rel industrial folks use. Senstron still exists as an acquisition of Antron Technologies.

Not vintage, but still relevant to the topic, I see lots of LCD monitors that are junked because they "come on for only a few seconds". Those are no-brainers and idenifying the bad caps is easy. Same goes for routers--I picked up an Actiontec MI242WR FIOS unit that looked to be bricked--the power light didn't come on at all and the JTAG input was dead. Replaced the bulging caps with fresh ones and the thing came right up and has been happy ever since.

Actually those LCD that turn on a few seconds and stop need a couple ICs replaced, my only LCD was snagged for free locally and fixed for a few dollars that way. Seems to be common in older models.

 

[chuckcmagee]

Crud, think I have enough LCD around, even for me. I did keep seeing listing on ebay that list exactly that - "turns on a few seconds and goes off". Does seem to be extremely common.

 

[Chuck(G)]

Actually those LCD that turn on a few seconds and stop need a couple ICs replaced, my only LCD was snagged for free locally and fixed for a few dollars that way. Seems to be common in older models.

I've done about 4 recently where the caps are bulging or leaking. The PSUs all look to be made by the same outfit, regardless of brand on the front. Usually, it's only a single value--the display sitting in front of me had bad 5 bloated 470 uF/25v caps (CapXon). The previous owner had said that he'd used it for only 6 months.

Badcaps.net documents similar atrocities.

But back to my question--is my assortment reasonable, or would you modify it? Any recommendations on brands (I've used Elna, Sprague and Nichicon up until now)?

 

[nige the hippy]

I'd limit the values myself, Caps have shrunk in size (physically), and generally speaking, what'll do a lot will do a little. Also you haven't got anything for the primary side. Although if I ever decide to buy a few spare anythings, I end up never using them again.

 

[Chuck(G)]

I'd limit the values myself, Caps have shrunk in size (physically), and generally speaking, what'll do a lot will do a little. Also you haven't got anything for the primary side. Although if I ever decide to buy a few spare anythings, I end up never using them again.

...Which is why I went for 16 and 35 V ratings and left out 10 and 6.3 altogether.

As far as primary caps go, 1000uF 200V caps are a serious investment that I'd prefer to buy on an "as-needed" basis.