List of good caps types/sizes to stock?

[goop]

Is there a list somewhere of "commonly used" capacitors of various V, C, ESR, dimensions, that are good to stock? Per device type, or just in general.

[Jooo]

Re: List of good caps types/sizes to stock?

No, but personally I keep these values in stock:
0.22uF 50V
0.47uF 50V
1uF 50V
2.2uF 50V
3.3uF 50V
4.7uF 50V
10uF 50V
22uF 50V
33uF 50V
47uF 50V
100uF 16V, 25V, 35V, 50V
220uF 16V, 25V, 35V, 50V
330uF 16V, 25V, 35V
470uF 10V, 16V, 25V, 35V, 50V
680uF 16V, 25V, 35V
820uF 25V
1000uF 10V, 16V, 25V, 35V
1200uF 25V
1500uF 16V
2200uF 10V, 16V
3300uF 16V

Might have forgot some values, but anyway, that should get you trough 90% of consumer electronics repairs, if capacitors are the problem. Remember to take low esr types, for power supply repairs, you should get away with Nichicon PW, NCC KY, Panasonic FM/FR.

[goop]

Re: List of good caps types/sizes to stock?

Thanks.

Do you keep multiple types (low ESR, normal...) of each capacitance/voltage combination?

What physical sizes do you go for? The lower voltage types are just for their smaller size?

Do the small capatiance ones really fail all that often?

What are the remaining 10% you use that aren't on the list?

Any preference to KYB over KYA?

[Jooo]

Re: List of good caps types/sizes to stock?

Thanks.

Do you keep multiple types (low ESR, normal...) of each capacitance/voltage combination?

What physical sizes do you go for? The lower voltage types are just for their smaller size?

I only have low esr capacitors, except for the 0.22uF caps. However in most cases you should be fine with general purpose capacitors on 0.22 - 4.7uF and probably up to 47uF too.

I mostly repair power supplies of various equipment, so most of my stock is Nichicon PW/PS, NCC KY or Panasonic FC/FM/FR which are sometimes called "entry-level low ESR" (not motherboard-grade, they don't work that well in power supplies).

I try to have multiple sizes of a single value, ie. I have about a thousand of 1000uF 25V 12.5mm dia in stock right now, but in some cases 12.5mm is too big, so I have about a hundred of 10mm dia 1000uF 25V too. The 12.5mm dia capacitors are much cheaper than the 10mm, so it is worth to have both sizes.

I like to replace the capacitors with their original values, so for that reason I have all voltage ratings that I have noticed to be needed the most often.

Do the small capatiance ones really fail all that often?

Yes yes yes. I always replace them. If you don't have ESR meter you absolutely need to replace them. They are often so small, that they dry out. They are dirt cheap too, so it is worth to have a larg-ish (depending on how much you repair electronics) stock of atleast 1uF, 2.2uF, 4.7uF, 10uF, 22uF, 33uF and 47uF (and 100uf and higher). You should have the other values too on hand, but smaller quantities are fine, as they are less common.

What are the remaining 10% you use that aren't on the list?

High voltage capacitors (main filter caps), uncommon values, obscure dimensions...

Any preference to KYB over KYA?

Haven't used them, but you can check the datasheet for differences.

[goop]

Re: List of good caps types/sizes to stock?

Thousands? I suspect you're using them much much more than I do. I just wanted to have a few, like 10-25 each, of the very most common types that are encountered, and that fail. I don't need them often, I will start by only replacing visually bad ones, and I don't mind reusing scavenged caps if they seem to work.

KYB is slightly better, but my impression is that in any case where KYB works, so will KYA. KYA is a bit cheaper, so I'm not sure what's the practical benefit to KYB.

Too bad in many cases the inventory of different part suppliers doesn't fully overlap.