Need ESR values for 8200uf 50v cap

[jimkarl]

Looking at power supply caps in in Rotel amp.

What is considered a good or ok ESR value for a 8200uf 50v Cap?
What would be consider a marginal or bad value?

All the esr charts I can find peter out at 4700uf....

[stj]

Re: Need ESR values for 8200uf 50v cap

make, series etc???

[jimkarl]

Re: Need ESR values for 8200uf 50v cap

They are marked Rotel with 9341 but my question is more general then specific to these.

[japlytic]

Re: Need ESR values for 8200uf 50v cap

From what I can see, these are the primary filter units.
A 8200uF 50V Chemi-Con KMH Series unit has a maximum ESR of 0.04 ohms at 120 Hz - most ESR meters typically measure only with 100 kHz.

[jimkarl]

Re: Need ESR values for 8200uf 50v cap

From what I can see, these are the primary filter units.
A 8200uF 50V Chemi-Con KMH Series unit has a maximum ESR of 0.04 ohms at 120 Hz - most ESR meters typically measure only with 100 kHz.

So two questions :
1) Is the esr expect to be higher or lower than that when measured at 100hz?
2) If that specific cap, as an example, read 0.08 ohms (twice the maximum), would it technically be considered "bad" or just out of ideal spec? I've posts where people consider anything above 1 ohm to be really "bad".

[pfofit]

Re: Need ESR values for 8200uf 50v cap

:... I've posts where people consider anything above 1 ohm to be really "bad".

That's just bad info. It's all relative.
A top speed of 140 Kph in a Lamborghini is "really bad", but normal for a ford ford focus.

It is dependent on several factors and asking what is the esr of XX uf @ xx V is not really answerable to any meaningful response.
Data sheet, data sheet, data sheet is the answer

Take this Vishay cap i ran into lately with an esr > 20.
Bad right?
But the data sheet says 32 ohms @ 10Khz. Go figure! see 1st pic
Extreme case, yes but there are others higher than 1 as normal for the right valve and series.
Even some low value Panny FC series has esr greater than 1. see 2nd pic
cheers


edited to clarily

[petehall347]

Re: Need ESR values for 8200uf 50v cap

i wouldn't worry too much in an amp .
look at something like this .
EPCOS Aluminium Electrolytic Capacitor 8200μF 80 V dc 35mm Through Hole series B41231 lifetime 2000h

[budm]

Re: Need ESR values for 8200uf 50v cap

I would get the one with highest ripple current and rated life spec for the application you are using it for: Linear power supply for power amp with high current demand.