Are these fake

[flewpastjupiter]

Hello, I recently bought these capacitors from Ebay from two different sellers, and I am not sure if they are the genuine article or not, does anyone have an eye for spotting fakes? as I cannot really tell. The capacitors are

5x Rubycon YXF - 50v 10uf

1x Chemi-con KY - 25V 3300uf

I measured the ESR and capacitance on them with my esr meter and it reads


five Rubycon YXF

capacitance-ESR
9.70..........0.60
9.50..........0.56
9.26..........0.58
9.62..........0.61
9.38..........0.64

The ESR on these Rubycons is too low according to the pdf which shows Impedence 1.5

********************************************************

Chemi-con KY

capacitance-ESR
3192...........0.00

According to the pdf manual the ESR on the KY should be 0.017, my meter never reads low ESR capacitors very accurately so the ESR seems about right for the KY.

Thank you for any help.

[mariushm]

Re: Are these fake

I don't think they're fake. The font looks good and clear, the plastic and well formed on the capacitors, the bottom cap looks good..

9 ohm esr is a bit much but we're talking about 10uF capacitors here.

At suck low capacitance and voltage combo, the ESR will be much different than impedance, so it's no wonder it's more than 1.5 ohm which is the impedance in the datasheet.

I wouldn't be concerned about it ... if esr was important, they would have used ceramic or tantalum capacitors for 10uF.

[flewpastjupiter]

Re: Are these fake

9 ohm esr is a bit much but we're talking about 10uF capacitors here.

I didn't write it very clear, the 9.5 and 9.6 etc was the capacitance of the caps, the ESR was quite low on them.