capacitor ESR table - different values from different manufacturers?

[smilem]

Hello, if you take a look at manuals of Atlas ESR70 meter and then Anatek BlueESR, two most respectable (and expensive) meters, you will see that their recommended capacitor ESR values are very different.

www.peakelec.co.uk/resources/esr70_userguide_en.pdf
http://www.mainelectronics.com/pdf/Blue ESR assembly manual.pdf

Now considering we are not paying money to measure with rubber ruler here, why such large difference?

For example 10uf 16v cap (blue esr 1.6ohms) and (atlas 16ohms) seems like a typo in the manual doesn't it?
For example 100uf 10v cap (blue esr 0.6uhms) and (atlas 2ohms) more than 2x difference.

So I just measured some caps from DVD-R unit (was working fine):

Brand,uf,voltage, in circuit esr, unsoldered esr, pass atlas, pass blue esr
Teapo 10uf 16v, 1.54, 1.57, 16 pass, 1.6 pass
Teapo 10uf 16v, 1.82, 1.80, 16 pass, 1.6 FAIL
Teapo 10uf 16v, 2.6, 2.8, 16 pass, 1.6 FAIL
Teapo 100uf 10v, 0.34, 0.50, 2 pass, 0.6 pass
Teapo 100uf 10v, 0.52, 0.52, 2 pass, 0.6 pass
Teapo 100uf 10v, 0.36, 0.0.56, 2 pass, 0.6 pass
CapXon 100uf 10v, 0.38, 0.98, 2 pass, 0.6 FAIL
Teapo 100uf 10v, 0.33, 0.0.56, 2 pass, 0.6 pass
CapXon 100uf 10v, 0.14, 1.10 2 pass, 0.6 FAIL
Teapo 100uf 10v, 0.33, 0.0.56, 2 pass, 0.6 pass
Teapo 47uf 16v, 1.34m 1.22, 3.5 pass, 2 pass
Teapo 47uf 16v, 0.43, 1.43, 3.5 pass, 2 pass
CapXon 220f 10v, 0.36, 0.50, 0.9 pass, 0.3 FAIL

Anyone knows who should I trust? I know I need to look into manufacturer data sheets, but for these caps it's impossible to find? Also why recommended values are so much different?

 

[davenn]

For a given value of capacitance, I would expect the ESR value to vary from manufacturer to manufacturer

BUT if for a given cap from a given manuf. and that say in the datasheet that the ESR should 1 Ω ± xx%, but you measure that
cap and it is substantially different. Then you would have to suspect that the cap is failing

Dave

 

[smilem]

So what chart is better? Caps are caps and there should be agreement what is considered low enough ESR for a cap to work properly.

(blue esr 1.6ohms) and (atlas 16ohms)
(blue esr 0.6uhms) and (atlas 2ohms) more than 2x difference.

These tables both seems like nonsense then, one of them is wrong.
If there is no baseline what caps are low enough ESR then what are we measuring again?

If capacitors are advancing and new caps have lower ESR, then respectable measurement equipment manufacturer should give tables by year. Usually on every equipment there is a sticker with model number and year, else you can just google the thing.

Anatek and Peaktek are not respectable measurement equipment manufacturer then, no such tables are provided.

But then what about the Agilent, Fluke etc.

 

[shrtrnd]

My experience is that mfgrs are CONSTANTLY changing materials in their caps. EVEN in the middle of production runs.
ALWAYS in an effort to save money, and sometimes to substantially improve electrical characteristics.
I'm pretty sure a particular production run has to meet the spec sheet parameter, but that's from their factory.
Once it leaves the factory, you may have minimum spec guarantees, but practical considerations come into play.
Temperature the caps are exposed to in vendor storage and delivery, other environmental factors that can affect capacitor characteristics, not to mention actual use in circuitry.
And yes. I've often found production runs I've received that don't meet the minimum spec sheet standards.
I use a Sencore Z-Meter to check ESR.
Depending on the year of equipment mfgr, maybe that's why you see variations in the test and measurement values of your ESR meters.
The specs on each year of capacitor production always seem to improve, but the actual quality control I see from those manufacturers is not reliable.
I'm with davenn in that we users need a minimum acceptable standard to go by, and if you test a cap that's out-of-spec by your ESR meters and mfgr specs, it's most likely bad.
I don't know what to tell you about your question about your ESR meters other than to check the mfgr spec sheet for the test equipment minimum specs.
Might be how old they are. Might be mfgr variance in spec sheet tolerances. (Not to mention calibration of the ESR instruments themselves.)

 

[smilem]

If you mean you use something like Sencore-LC101 that's one heck of a meter !
10x more range than Atlas ESR70, and I'm not speanking that Sencore can measure from 1pF to 200,000 μF

Getting back on topic here, yes there should be standard for ESR values, now it seems the Blue ESR table is really more logic with real world values than Atlas ESR70 manual table.

I was given this link at badcaps forum http://www.paullinebarger.net/DS/
All I can say it's a life saver !

Now if only can I find Rubycon YXB series data sheets.

 

[Bodragon]

The ESR table for the BlueESR is for NEW capacitors. NEW being UNUSED.
The other table, the Atlas one gives just "TYPICAL" values for USED capacitors.
There is your answer for the difference.

 

[caps]

There is your answer for the difference.

No one knows the clearance distance.

 

[bertus]

Hello,

Here is some info on the ESR value on the capsite:
http://www.iequalscdvdt.com/esr.html
It also shows the relation between ESR and frequency.

Bertus

 

[caps]

Hello,
Routine.

 

[(*steve*)]

I think an important fact is that there is no particular value of ESR that is ok, vs some other value that is bad for some combination of voltage rating and capacitance.

My conjecture is that you'll find lower ESR values quoted in newer tables, simply because more modern capacitors have lower ESR's.

The two factors that are the most important are (firstly) the range of acceptable ESR values that can be tolerated in a circuit. Yes, there are some cases where the ESR can be too low. The second factor is the manufacturer's specification for ESR. A completely acceptable value of ESR for one "low ESR" capacitor might be unacceptably bad for another.

The best that tables can do are to represent values for some type of circuit designed for some oft used type of capacitor, or conversely for acceptable value for current capacitor designs.

The manufacturing processes for capacitors, and the design of circuits to take advantage of advances in the manufacture go hand in hand to make simple tables, at best, some sort of heuristic valid at the time the table was compiled.