Using an ESR Meter (and Reference Chart)

[lkvee]

I just got my ESR Micro 3.1

I'm having fun testing out all sorts of capacitors with it. I always remember to discharge 'em before testing 'em.

I'm wondering about the reference charts that give a ballpark maximum acceptable ESR.

When I get a reading of 0.00 of 0.01 Ohms, I'm happy enough once I identify a reputable brand on the capacitor.

When I get a reading of 25 Ohms, I'm happy because I know I can extract it and discard it.

I'm wondering about the next steps once I identify a cap whose ESR hovers around that acceptable number.

Most of the reference charts I've seen list discreet readings for capacitance, voltage, and ESR. I can't find a mathematical formula that can let me input the nominal capacitance and voltage and spit out the maximum acceptable ESR. I know this formula will vary from meter to meter, and I'd be happy to use Bob Parker's formula, too.

Thx 4 reading!

[steve2]

Re: Using an ESR Meter (and Reference Chart)

This is from the Blue ESr meter meter manual.
What is bad ESR?
There is a chart of 3 X normal average ESR for various capacitor values and voltage ratings on the meter front
panel. There is no one bad value; it depends upon the rating of the capacitor you are testing.
In general, a capacitor with bad ESR will read at least 2 – 3 times the values given for a new capacitor by the
manufacturer. The values shown on the chart are generally 3 times the manufacturer’s specs. A really bad one
might be 10 times the values shown or more.
With experience you will be able recognize bad ones without consulting the chart.

[bp1]

Re: Using an ESR Meter (and Reference Chart)

I just got my ESR Micro 3.1

I'm having fun testing out all sorts of capacitors with it. I always remember to discharge 'em before testing 'em.

I'm wondering about the reference charts that give a ballpark maximum acceptable ESR.

When I get a reading of 0.00 of 0.01 Ohms, I'm happy enough once I identify a reputable brand on the capacitor.

When I get a reading of 25 Ohms, I'm happy because I know I can extract it and discard it.

I'm wondering about the next steps once I identify a cap whose ESR hovers around that acceptable number.

Most of the reference charts I've seen list discreet readings for capacitance, voltage, and ESR. I can't find a mathematical formula that can let me input the nominal capacitance and voltage and spit out the maximum acceptable ESR. I know this formula will vary from meter to meter, and I'd be happy to use Bob Parker's formula, too.

Thx 4 reading!

I use the the attached which i got from the ESR Micro V4 documentation.
I have a copy of that laminated to a credit card size which i keep with my ESR Micro.

Hope it helps you to.



Kind Regards
bp1

[david38c63]

Re: Using an ESR Meter (and Reference Chart)

I have a question What is the recommend ESR for 33uf at all voltages?

[ipman]

Re: Using an ESR Meter (and Reference Chart)

ESR is not the same for a capacity at different voltages.

[KeDase]

Re: Using an ESR Meter (and Reference Chart)

Why is there no reference on charts with lower volts, such as (6.3V) or higher (400-450V)
I have a blue esr meter, but i suck on reading the chart thats on it :-(

[Agent24]

Re: Using an ESR Meter (and Reference Chart)

I don't know but I think the chart is just a general guide.

Different capacitor series are going to have different ESR values, if you want to know what a specific capacitor's ESR value *should* be - check the datasheet.

[Th3_uN1Qu3]

Re: Using an ESR Meter (and Reference Chart)

General guideline:

Primary caps 220u and up: 100-200mOhms depending on size and value.
Power supply caps 1000u and up: 30-60mOhms
Motherboard caps 820u and up: 5-40mOhms; most are in the range 10 to 30.

[budm]

Re: Using an ESR Meter (and Reference Chart)

I would go with the datasheet provided by the manufacturers of the caps, I.E. you can see that PANASONIC FC spec is not the same as FM, or FR series.
The circuits designer will also have to pick what they want to use base on the circuits requirement.

[SM-Piyes90]

Re: Using an ESR Meter (and Reference Chart)

How about this one , 68 uF 400V TEAPO , used as primary filter .

[izzzzzz6]

Re: Using an ESR Meter (and Reference Chart)

Hi, i came here as i am testing a power supply smoothing capacitor which seems to have bulged, I can't find any test charts that cover the values.
I will go to check the data sheet to see if i can estimate weather or not it is still good but i am not sure what the acceptable difference in value should be.
At first glance the cap still seems to be acceptable. It is a 400V 180uF 85C
25mm * 35mm 10mm lead gap.

The reading i get is ESR 0.27ohms Vloss=1.2%
161.7uF

I can't find the data sheet for the Yageo capacitor i have but a similar capacitor from Panasonic shows 20C ESR readings to be .737 at 120Hz and .332 ohms at 20kHz
I really am a bit lost here. I would say my cap is ok but is has bulged so i've bough a new one, was it necessary?
The fuse holder in the power supply had melted out of shape and the fuse eventually blew. It is the power supply for a 20ch band mixer, it was working but had started to smell funny till finally it stopped working during a recording session. Seems to be working again now with the fuse repaired and the old cap in place but i'm awaiting the new cap just incase. I think the fuse holder was arcing, perhaps due to extra strain caused by the bad cap or perhaps the cap went bad (or did it) due to the fuse arcing? It's just a guess. Hopefully the mixer will be fully repaired shortly.

[Agent24]

Re: Using an ESR Meter (and Reference Chart)

If it has bulged then it's damaged in some way, replace it anyway.

However, being a 400V rated capacitor, it may have a plastic cover on top of the can, under the sleeve. These are normally often not flat and have nothing to do with the capacitor itself.

To know for sure - remove the plastic cover, if the metal can is bulging underneath then the capacitor is bad.

[Kiriakos GR]

Re: Using an ESR Meter (and Reference Chart)

I really am a bit lost here.

Freeze it with spray and measure it capacity again.
If the capacitor is half dead, it will be shown.

[Kiriakos GR]

Re: Using an ESR Meter (and Reference Chart)

General guideline:

Primary caps 220u and up: 100-200mOhms depending on size and value.
Power supply caps 1000u and up: 30-60mOhms
Motherboard caps 820u and up: 5-40mOhms; most are in the range 10 to 30.

And I will add that all these measurements they require a meter with four digits display resolution, and accurate milliohm measurement with Kelvin type test leads.

Therefore cheap ESR meters are incapable to serve this goal.

[SteveNielsen]

Re: Using an ESR Meter (and Reference Chart)

Cheap ESR meters have valid uses and not everyone can afford the best. Getting a relatively good idea of ESR is better than getting none. How much difference is up to .009 ohms ESR one way or another going to make in a circuit anyone here is going to work on?

[Kiriakos GR]

Re: Using an ESR Meter (and Reference Chart)

With out an true LCR meter at hand you may not even build an stereo amplifier that both channels will have the same volume output or frequencies response.

Or even confirm that the capacitors which you got from eBay are genuine or not.
Capacitors is an important electronic part, build under strict specifications that cheap ESR meter can not measure for all reasons mentioned all ready.

In electronics with out the proper tool at hand you can not work at all.
Therefore by getting what is needed you can finally do some work and earn money.
And finally why are you nagging to others .. when you may start saving money and buy something worthy in six months from now?
Now one got all the necessary tools for him in a day.

[SteveNielsen]

Re: Using an ESR Meter (and Reference Chart)

Oh crap! That just tears it. I will never, EVER work on anything electronic again because I don't have and cannot afford Kiriakos Approved test equipment. My life is ruined now.
Show me where I have nagged anyone.
You're a snob. Keep up the attitude and I'm sure you'll get sent to the corner again.

[stj]

Re: Using an ESR Meter (and Reference Chart)

Or even confirm that the capacitors which you got from eBay are genuine or not.

if you can afford a meter, you dont buy caps on ebay!

[stj]

Re: Using an ESR Meter (and Reference Chart)

actually let me correct that.

if you can only afford to buy caps on ebay, you still DONT buy caps on ebay!!!

[SteveNielsen]

Re: Using an ESR Meter (and Reference Chart)

I've never bought anything on ebay.