What's the rule for Poly mods? (Half the capacitance?)

[PCBONEZ]

Re: What's the rule for Poly mods? (Half the capacitance?)

I understand.

I need a 10uF cap and 4 22uF caps.


They are all rated for 25V currently, though my multimeter shows that <5V are running through them at any given time. But I suppose, what's the difference...

So for replacements. For the 10uF, I'm looking at a 50V Nichicon PM and for the 22uFs, I'm looking at some 50V Panasonic FRs.

Are Nichicon PMs any good for motherboard/PCI card use?


The name of the capacitor company on the card is TWBOR. Not sure if you've heard of them. http://www.twbor.com/Enproduct.asp

In regards to ESR, the bigger the capacitor, the less the ESR?

TWBOR is crap.

I agree FC are better than PM. [And FC are usually cheap.]
FR should be fine.

They often use over rated [on the voltage] caps to get better ESR or better Ripple ratings.

""In regards to ESR, the bigger the capacitor, the less the ESR?""
If they are an equivalent 'grade' then yes.
-
Like Rubycon ZL is 'spec equivalent' to Chemicon KZE.
A larger cap in either of those will have lower ESR and higher Ripple ratings than a smaller one. [Of either of those.]
- But:
A higher grade cap [like say Rubycon MCZ] will have better ESR and Ripple ratings even if the can is the same size.
.

I thought of a way to show it. Will take me a bit to work it up.
.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

TWBOR is crap.

I agree FC are better than PM. [And FC are usually cheap.]
FR should be fine.

They often use over rated [on the voltage] caps to get better ESR or better Ripple ratings.

""In regards to ESR, the bigger the capacitor, the less the ESR?""
If they are an equivalent 'grade' then yes.
-
Like Rubycon ZL is 'spec equivalent' to Chemicon KZE.
A larger cap in either of those will have lower ESR and higher Ripple ratings than a smaller one. [Of either of those.]
- But:
A higher grade cap [like say Rubycon MCZ] will have better ESR and Ripple ratings even if the can is the same size.
.

I thought of a way to show it. Will take me a bit to work it up.
.

Very well put PCBONEZ. I understand the concept much better now.

[PCBONEZ]

Re: What's the rule for Poly mods? (Half the capacitance?)

When comparing 'grade' look at the same size cap between series.
I use 8x20mm, 10x20mm, and 12.5x20mm both out of habit and because most all series have those sizes.

Look at can size, ESR, and Ripple in my doctored data sheet screen shots.
- First notice that they even have a "Can Size / ESR / Ripple chart".
- That's because ESR and Ripple are based on the Can Size - WITHIN EACH SERIES.

-
You will notice that FR and FM are the same 'grade'. [apart from a slight difference in the 10mm ESR]

FC are lower grade.

In -each series- as can size goes up the ratings get better.

However, the FC is a far enough lower grade that the 10x20mm FC is rated lower than the 8x20mm FR and FM. [Even though it is larger.]
.
.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

When comparing 'grade' look at the same size cap between series.
I use 8x20mm, 10x20mm, and 12.5x20mm both out of habit and because most all series have those sizes.

Look at can size, ESR, and Ripple in my doctored data sheet screen shots.
- First notice that they even have a "Can Size / ESR / Ripple chart".
- That's because ESR and Ripple are based on the Can Size - WITHIN EACH SERIES.

-
You will notice that FR and FM are the same 'grade'. [apart from a slight difference in the 10mm ESR]

FC are lower grade.

In -each series- as can size goes up the ratings get better.

However, the FC is a far enough lower grade that the 10x20mm FC is rated lower than the 8x20mm FR and FM. [Even though it is larger.]
.
.

Even better. Thanks. This would be helpful almost in a FAQs section or stickied.

[PCBONEZ]

Re: What's the rule for Poly mods? (Half the capacitance?)

What is better than what gets trickier as the grades get closer together because different series' might have different Can Sizes.
.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

Well, I kind of forgot about this recapping thing for a while.

Today I was on Mouser, just perusing....

I just wanted to see how much it would be to ship it, because one time, I got charged like $12 to ship like a 10 x 7805s...

Yeah.....and I accidentally hit the checkout button and bought the caps.

Good thing I removed that $40 transformer from my cart before I hit the button. I don't know how I accidentally hit it, but I did.

And Mouser has no option for cancelling orders..I'd have to actually call them or something. (Pssh...human interactions.)

So, yepp....I have a few caps coming in the mail. Hopefully I don't screw over my card.

First recap.

[mockingbird]

Re: What's the rule for Poly mods? (Half the capacitance?)

Actually I found Mouser to have the cheapest shipping of anyone to Canada (Only $8).

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

Actually I found Mouser to have the cheapest shipping of anyone to Canada (Only $8).

Yeah I guess that must have been a while ago when I got charged $12. This order was only $4.50 shipping.

So, it's no big deal.

Still want to do a poly mod though...

The caps I ordered were 1 Panasonic FC and 4 Panasonic FRs.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

Do you guys really think the one FC cap is not going to work? (In terms of ESR)

It's about triple the size of the cap it will be replacing. The cap it is replacing is a beautiful Cheng cap. . I can't imagine that the Cheng cap is any better...

[smason]

Re: What's the rule for Poly mods? (Half the capacitance?)

Actually I found Mouser to have the cheapest shipping of anyone to Canada (Only $8).

Digikey is $8.00 as well. Though they seem to have recently switched to fedex, who are great a f-ing things up.

[mockingbird]

Re: What's the rule for Poly mods? (Half the capacitance?)

Digikey is $8? Odd, they usually charge me $10. Their stock is a little disappointing as of recent. I wish they or Mouser would start stocking Panasonic FK.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

Any ideas on that FC?

[mockingbird]

Re: What's the rule for Poly mods? (Half the capacitance?)

FC will work if the rating is a lot higher and thus the ESR usually matches the lower rated part.

What worries me about using much higer rated caps though is that there isn't enough current to disolve the foil and it may not perform properly, though my logic may be in error.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

FC will work if the rating is a lot higher and thus the ESR usually matches the lower rated part.

What worries me about using much higer rated caps though is that there isn't enough current to disolve the foil and it may not perform properly, though my logic may be in error.

Ahh....I see....Any one else have any thoughts.

Thanks by the way.

[TheLaw]

Re: What's the rule for Poly mods? (Half the capacitance?)

Anyone?