capacitor ripple vs endurance & other questions

[GameBooy2020]

Hello, I have a few questions regarding some of the specifications found on capacitor datasheets.

1.) Which specification of capacitors is more important, endurance or rated ripple? Nichicon HE capacitors have a higher endurance rating than HZ, so wouldn't they be better?

2.) Not all data sheets list esr, so how can I tell what capacitor would be better than another one?

3.) Nichicon HZ capacitors have a higher ripple rating than Rubycon MCZ capacitors, so would the nichicon HZ be better than the Rubycon in this case?

4.) Also, what range would be considered a good esr reading, and what range would be considered bad?

Thanks for taking the time to review my post!

[Toasty]

Depends on application is the key. Endurance is for X hours @ rated temperature @ rated ripple & voltage. That is not a typical operating condition. Typical would be < 60% of temperature and weighed across the life of the cap. The number escapes me but it is exponential in value as to the increase in lifetime for each X degree decrease from rated maximum. A 2,000 hour 105°C cap running at 60°C could easily last 10 years or more.

Impedance & ESR are essentially the same thing. Look for that instead. Again, application determines which cap is better suited.

For their particular use, I would say yes ~tentatively~. Either would work fine in the same application. CPU VRM for instance.

Again, application determines what is good vs. bad and what cap you are testing. You need the info on the original cap to determine good/bad.

Read the forums. There are ~years~ of information. Start with the FAQ's and work out from there. Not everything is a quick answer.

Cheers & Welcome!
Toast

[GameBooy2020]

Hey thanks for replying!

So even though endurance is not tested in a typical operating condition, wouldn't a capacitor rated at 4000 hours @ 105C be better than a capacitor rated at 2000 hours @ 105C? I've been repairing a few monitors & video cards lately using capacitors that I picked up at a local electronics store, but I want to start using the most reliable capacitors possible for my repairs (I was planning to buy some of the mcz and mbz rubycons from here, but rubycon doesn't make that line in the capacitance & rated voltage that I need & I wanted to see if I could find something better). Basically, I just wanted to know why most people here consider the Nichicon HZ capacitors to be better than the HE ones even though they have a longer life.

[Toasty]

>>but rubycon doesn't make that line in the capacitance & rated voltage that I need<<

???

Give some values so we can steer you in the right direction.

>>using capacitors that I picked up at a local electronics store<<
Specifics instead of "generalities" please. What you obtained may not be correct for the unit you're fixing.

Toast

[GameBooy2020]

I apologize, here are the values of the capacitors that I need and the sizes as well:

330 uf @ 16 V ----------- 8 x 12 mm
1000 uf @ 6.3 V ---------- 10 x 12 mm
1000 uf @ 10 V ---------- 10 x 16 mm
470 uf @ 25 V ---------- 10 x 16 mm
470 uf @ 10 V ----------- 8 x 11.5 mm
1000 uf @ 16 V ------------ 10 x 20 mm

[PCBONEZ]

.
Endurance "Lifetime" is the number of hours @ max rated temperature & @ max rated ripple [at the stated frequency] & @ max rated voltage that the cap can be subjected to - AND - still have ~all~ values within advertised specs when returned to nominal conditions.
-
In other words it's how long you can abuse the F**k out of it and cause zero damage.

The Endurance value is of no PRACTICAL use because if you never operate the cap at those conditions that number is useless information.
[ And if you -tried- to operate a mobo cap even close those conditions it wouldn't boot and some bits here and there might even melt. ]

Some people think they can calculate an expected Lifetime from it but those equations are only accurate to within +/-40%.
8 years +/-40% => 4.8 years to 11.2 years. [NOT useful information!]

.

[PCBONEZ]

Originally Posted by GameBooy2020

Hey thanks for replying!

So even though endurance is not tested in a typical operating condition, wouldn't a capacitor rated at 4000 hours @ 105C be better than a capacitor rated at 2000 hours @ 105C?

As I said, endurance tells you nothing useful about actual lifetime.

For the explanation lets say all the caps other characteristic are the same such that the useful lifetime follows the endurance lifetime.

As so:
Cap 1 - 2000hr => 6 year useful lifetime
Cap 2 - 4000hr => 12 year useful lifetime.

But because of the +/-40% accuracy...
6 years really means from 3.6 to 8.4 years and useful lifetime would be as expected.
12 years really means from 7.2 to 16.8 years and useful lifetime would be as expected.

Every single Cap 2 could fail at 7.2 years.
Every single Cap 1 could last 8.4 years.

Did the Endurance number help you? - NOPE!

.

[PCBONEZ]

Originally Posted by GameBooy2020

I apologize, here are the values of the capacitors that I need and the sizes as well:

330 uf @ 16 V ----------- 8 x 12 mm
1000 uf @ 6.3 V ---------- 10 x 12 mm
1000 uf @ 10 V ---------- 10 x 16 mm
470 uf @ 25 V ---------- 10 x 16 mm
470 uf @ 10 V ----------- 8 x 11.5 mm
1000 uf @ 16 V ------------ 10 x 20 mm

What make and series were the old ones?

What is the application?

.

[GameBooy2020]

I see, so endurance is practically useless, thanks for clearing that up for me.


here's a list of the old capacitors that I plan to replace:

brand -------- specs

elite PF ------ 1000uf @ 16V ( 10 x 20 mm)
capxon KF --- 1000uf @ 10V ( 10 x 16 mm)
capxon KF --- 470uf @ 10V ( 8 x 11.5 mm)
capxon KF --- 470uf @ 25V ( 10 x 16 mm)
skywell SHT - 1000uf @ 6.3V ( 10 x 12 mm (not sure about height since I could'nt find datasheet for SHT) )
Sacon FZ ---- 330uf @ 16V ( 8 x 12 mm)


The capxon's and the elite are from lcd monitor power supplies, and the skywell & sacon caps are from video cards (AGP).

[mockingbird]

KF I replace with UCC LXZ or LXY

[PCBONEZ]

The ratings to look at beyond uF and volts are ESR and Ripple.
[Remember going up in volts isn't a problem.]

ESR is isn't really Impedance (Z) - but:
At the 100kHz they use for data sheets Xc and ESL are at values such that *effectively* ESR = Impedance.
The actual equation is:
Z² = ESR² + (XL - XC)²
[Note: (XL - XC) must be corrected to a positive value if it isn't.]
-
ESR is effectively a measure of the cap's 'resistance' to AC Ripple.
Since the cap's job is to short Ripple out to ground: lower is better.

The 'Ripple' rating tells you how much Ripple current the cap can pass without overheating internally.
It is the capacitor equivalent of a watt rating on a resistor.
It tells you how 'heavy duty' the cap is and thus: more[higher] is better.

elite PF ------ 1000uf @ 16V ( 10 x 20 mm) - General Purpose cap - Ripple = 680
Rubycon PX @16v is not rated good enough.[Ripple = 640]
I would use something like LXZ, LXY, VZ, FC, PW

Capxon KF --- 1000uf @ 10V ( 10 x 16 mm) 1040 / 0.076
Panasonic FC is just good enough for this one. [KF specs are not linear, so to speak.]
Use FC or better.

capxon KF --- 470uf @ 10V ( 8 x 11.5 mm) 580 / 0.250
capxon KF --- 470uf @ 25V ( 10 x 16 mm) 1200 / 0.076
These are rated better than FC.
Chemicon KY or Nichicon HE are good enough.
Chemicon KZE and Rubycon ZL are the next better grade.

Sacon FZ ---- 330uf @ 16V ( 8 x 12 mm) - 1150 / 0.036
Pannasonic FM is not good enough. [950 / 0.056]
Use Rubycon MBZ or MCZ - Panasonic FJ or FL - Sanyo WG.

skywell SHT - 1000uf @ 6.3V ( 10 x 12 mm (not sure about height since I could'nt find data sheet for SHT) )
I would treat this the same as the FZ to be safe since I can't find a spec sheet either.

.

[mockingbird]

Thank you. This was very helpful. I've been struggling to understand why people recommend which series for what.

One question though. When are you recommending KZE and MBZ/MCZ?

This is the way I understand it. KZE and MBZ/MCZ are Low ESR and high ripple caps. So you use them in places where low ESR is required like a motherboard's VRM. Would you put KZE let's say on a power supply?

[Toasty]

He's only posted that info ohhhh 50 times now......

There is also a chart PC did on replacements based on application and quality/ratings. Buried in another thread and posted within past year IIRC. If I find it, I'll put the link here.

[Toasty]

Here:

http://www.badcaps.net/forum/showpos...11&postcount=4

I did my own chart based on his info using only readily available caps from USA suppliers. No types that are N/A in US without extraordinary effort. Like Pana FJ or FL.

[PCBONEZ]

Originally Posted by mockingbird

Thank you. This was very helpful. I've been struggling to understand why people recommend which series for what.

One question though. When are you recommending KZE and MBZ/MCZ?

This is the way I understand it. KZE and MBZ/MCZ are Low ESR and high ripple caps. So you use them in places where low ESR is required like a motherboard's VRM. Would you put KZE let's say on a power supply?

KZE is in fact intended for PSU according to Chemicon.

Looking at 8x20mm

MCZ: .................... 2350 / .012
FL & FJ: ................. 1870 / .016
MBZ & WG: ........... 1870 / .019
FM: ....................... 1560 / .030
KZE, ZL, WX, HD: . 1250 / .041
KY, HE: ................. 1050 / .069
FC, PW: .................. 995 / .065
LXZ: ....................... 810 / .080

The 10x20mm follow the same pattern.

In Vcore and RAM:
KZE was the typical grade on PC133 motherboards.
By DDR RAM MBZ was more typical.
- It varies with how many cap are used because caps in parallel lowers total circuit ESR.

KZE grade is still common for the 8 & 10 mm caps used out near the add-in slots when the board has 6 or more caps out there.
Low cap-count boards will use higher grades.

.

[GameBooy2020]

Thank you. This was very helpful. I've been struggling to understand why people recommend which series for what.

Yeah same here, the information everyone has placed here has helped me alot. I finally understand what all of the values are and what they do now. Thanks guys!

[mockingbird]

WOW!! KZE is higher ESR than FM!!!! Is KZG any better? Sorry for not looking at the spec sheets myself, I don't understand how to calculate ESR from a spec sheet.

[yyonline]

Originally Posted by mockingbird

WOW!! KZE is higher ESR than FM!!!! Is KZG any better? Sorry for not looking at the spec sheets myself, I don't understand how to calculate ESR from a spec sheet.

KZG is equivalent spec-wise to MBZ/WG. However, it's not recommended for recapping purposes has KZG is prone to failure.

[Toasty]

Originally Posted by mockingbird

WOW!! KZE is higher ESR than FM!!!! Is KZG any better? Sorry for not looking at the spec sheets myself, I don't understand how to calculate ESR from a spec sheet.

Calculate? There is no calculate. Just read the datasheets.

[Toasty]

Here: