Rubycon Caps

[a1guitarman]

I just got some Rybycon caps 220uf 35v and they all read 200uf .3 ESR

(Atlas ESR70 test meter)

Are they OK ?? I'm trying to learn. I don't know yet, the min max readings allowable and haven't been able to find a general kind of chart or something.

Should I be looking at Nichicon from Mouser and if so, and I wanted to use say 105 degree, there's a boatload to choose from and I don't know how to choose yet... My amature knowlege showing up here :>)

Any help appreciated.

[mariushm]

Re: Rubycon Caps

Rubycon is a quality manufacturer, just like Nichicon, United Chemi Con, Panasonic etc

0.3 ESR is also OK, maybe a bit high but not uncommon - the ESR value usually goes up as the capacity and the cap. dimensions go down so for example for a 47uF capacitor can be 0.5-1 ohm ESR while a good 1000uF capacitor should have about 0.05-0.15 ohm

The impedance and ripple values are usually listed in the datasheets - it's important to have lower or equal impedance and higher or equal ripple values compared to the capacitors you replace.

I believe the ripple value is not that important but it's good to respect it - often the value is very high because the capacitor with such high value happens to also have a low impedance value and that's why it was chosen - the circuit it's in probably never produces so much ripple.
For example, there are capacitors on video cards with ratings of 2400-3000 mA. If the power supply delivers such poor quality power to the card the user has serious problems.

[retiredcaps]

Re: Rubycon Caps

I just got some Rybycon caps 220uf 35v and they all read 200uf .3 ESR

Rubycon makes many series of caps. Some are general purpose, some low esr, some very low esr.

On the cap, there will be a 3 letter code. It might be MCZ, MBZ, etc. Look for that datasheet and compare your reading to the ESR reading on the datasheet.

[a1guitarman]

Re: Rubycon Caps

Thanks again for the info.. every little bit helps.

Soooo.. is 198uf to 200uf acceptable for a NEW 220uf cap or should I return them?

I have other caps of different mfg and values, some of which are over stated values, and like these, under. I'm just trying to get a grip on all this, as I'm a newbie..

I have successfully repaired about 30 laptops, and around 20 LCD monitors. Mostly Bad Caps, and a couple CCFL fixes. I'm hoping to learn enough to open a small business in my little home town because there is nobody around here that does it. I don't mind the lappys, but I think I'd like to stick with LCDs and maybe LCDtv. Haven't done a TV yet.

Tools:
HAKO 936
R.S. Hot solder sucker
Atlas ESR70
Hot Air station
Fluke 115
Kester 186 pen

Again, thank you for you help !!

[mariushm]

Re: Rubycon Caps

The majority of capacitor series have a 20% variation or "tolerance" from the factory so a 220uF can be anything between 180 and 240 uF.

The standard values of capacitors are intentionally chosen in such a way that they slightly overlap...

[a1guitarman]

Re: Rubycon Caps

Thank You very much !!