ESR meter 200kHz

[tigr]

Measurement ESR of capacitors:electrolytics,films,ceramics,polymer.
ESR-0,001-30Ohm
F-200kHz
Ut-100mV
VD1,VD2-1N4007
VD3-VD6-1N5819
C2-2,2uF/63v(film)
R2-0,18Ohm
R5-100k
C3(removed)
T1 1-40/2-200
PA1-0,05-0,1mA
U-5v

[hugo]

Hi Tigr,

What is the benefit of using 200kHz instead of the more traditional 100KHz ?
What kind of transformer is T1 " T1 1-40/2-200" ?
R2-0,18 Ohm that is not right to me ...

Thanks

[tigr]

Hi hugo.
This frequency is chosen because the circuit working at this frequency. The transformer can be wound with a wire of 0.1-0.15 mm or use a ready one. The resistor R2 can be used 5-0.05 Ohm.
Transformer from my latest version.Removed from some power supple.The ratio of the windings is 1:40.The wire is 0,3mm.
R5-100k

[tigr]

Microammeter. You can use different.
50u-100uA.

[tigr]

Measurement ESR of capacitors:electrolytics,films,ceramics,polymer.

[tigr]

The main feature of this ESR meter is the search for faulty film capacitors of low capacitance in the circuit.

[tigr]

About ESR.
https://www.allaboutcircuits.com/technical-articles/determining-equivalent-series-resistance-esr-of-capacitors/

[tigr]

Experimental version for ESR 350kHz for ceramic capacitors.
Transformer from the old Sony TV.

[tigr]

Using Tweezers MAX 253, you can measure esr of capacitors of large capacitance.
Capacitors MKT-15uF.
ESR~0,001Ohm.

[b_force]

Hi Tigr,

What is the benefit of using 200kHz instead of the more traditional 100KHz ?
What kind of transformer is T1 " T1 1-40/2-200" ?
R2-0,18 Ohm that is not right to me ...

Thanks

Better sweep a range from a few hertz to a few Mhz to get the total impedance.
Why? To get a better idea how capacitors perform at certain frequencies.
I have seen caps that worked great around 100kHzish, but failed bad if you would go somewhat higher.

[tigr]

More examples of the measurement of ESR for high-capacity film capacitors.

[tigr]

What is the benefit of using 200kHz instead of the more traditional 100KHz ?

The difference in ESR at these frequencies is minimal.

[b_force]

What is the benefit of using 200kHz instead of the more traditional 100KHz ?

The difference in ESR at these frequencies is minimal.

Well, the impedance is clearly different.
Also really depends what kind of capacitor you have.
I have seen (and used) ones that are much worse (also much better)

[tigr]

In datasheets for polymer capacitors, only indicate the ESR at a frequency of 100-300kHz.

[tigr]

The quality of the dielectric of film capacitors depends on the ESR. This can be verified by measuring different capacitors of 100nF.

[tigr]

The inductance of the windings of the transformer is 200 kHz.

[tigr]

Tweezers Max 253 always helps in complex cases of measurements in the circuit.
 The computer power supply. The capacitor is 2200 mkF 10V.
ESR-0,008Ohm.

[ocw]

Have I missed the accuracy verification?  All of these numbers are nice but if they are not accurate they are meaningless.

Right now I'm testing an economy Ragu 17B multi-meter that I've just received.  For resistance accuracy verification I'm using 0.01% accuracy resistors that range in value of 10 ohms to 10M ohms.  For resistances below 10 ohm I'm using 0.05 or 0.1% accuracy resistors.

[tigr]

And the resistor 0.001 Ohm 1% is not enough? Something I have not seen anywhere, that this resistor was checked by the ESR meter.
They correctly show the measurement of resistors 0.001 Ohm and 0.01 Ohm.
Resistor 0,001Ohm 1%.

[ocw]

And the resistor 0.001 Ohm 1% is not enough?

That reading looks believable.  Sorry.  I hope that your ESR meters and your 200 kHz tests show the same thing.  Two wire readings of a fraction of an ohm to an analog meter have me wondering though.

[tigr]

Resistor 0,001Ohm 1%.

[The Electrician]

More examples of the measurement of ESR for high-capacity film capacitors.

I very much doubt that the Epcos 15 uF MKT capacitor shown here could have an ESR as low as .001 ohms.

See the data for this capacitor here: https://en.tdk.eu/inf/20/20/db/fc_2009/B32520_529.pdf

On page 21 we see that the typical ESR for a 15 uF capacitor is about .01 ohms, not .001 ohms.

I have no doubt that your meter can measure .001 ohms for a pure resistor, but not for a real capacitor.

If I correctly read the schematic in post #1, the circuit of your meter has no phase sensitive detector so it is measuring the magnitude of the impedance (|Z|) of a capacitor, not the real part of the impedance which is the ESR.

[tigr]

If I correctly read the schematic in post #1, the circuit of your meter has no phase sensitive detector so it is measuring the magnitude of the impedance (|Z|) of a capacitor, not the real part of the impedance which is the ESR.

Everything perfectly measures.
The polymer capacitor OS-CON SVP 820uF/6,3V ESR(max.)-0,012Ohm.
http://uk.farnell.com/panasonic-electronic-components/6svp820m/cap-alu-elec-820uf-6-3v-smd/dp/2354726
Tweezers MAX253.ESR~0,007Ohm.
More accurately.
Tweezers ESR-TIGR.ESR-0,0065Ohm.

[The Electrician]

If I correctly read the schematic in post #1, the circuit of your meter has no phase sensitive detector so it is measuring the magnitude of the impedance (|Z|) of a capacitor, not the real part of the impedance which is the ESR.

Everything perfectly measures.
The polymer capacitor OS-CON SVP 820uF/6,3V ESR(max.)-0,012Ohm.
http://uk.farnell.com/panasonic-electronic-components/6svp820m/cap-alu-elec-820uf-6-3v-smd/dp/2354726
Tweezers MAX253.ESR~0,007Ohm.
More accurately.
Tweezers ESR-TIGR.ESR-0,0065Ohm.

It is entirely possible for a meter than doesn't have a phase sensitive detector to correctly measure the ESR of a capacitor if the capacitor is rather lossy.  This is because at frequencies near the self resonant frequency of the capacitor, the impedance (Z) is essentially the same as the real part (Rs) of the impedance.  This is because the curve of impedance versus frequency has a broad minimum, as shown in your image in post #11.  I explain this here: https://www.eevblog.com/forum/projects/impedance-lcr-esr-meters/msg459262/#msg459262 and in the posts following.

But when measuring a low loss film capacitor, the curve of impedance versus frequency has a sharp minimum like this:



The ESR is equal to the impedance at the very bottom of the sharp impedance versus frequency curve, and if the measurement of your meter is at that frequency, then it will measure the ESR; otherwise, it will measure the impedance which will be larger than the ESR.

So, to summarize, a meter that measures impedance (Z) rather than ESR will do what is wanted if you are measuring lossy capacitors such as electrolytics and if your measuring frequency is around 100 kHz plus or minus a bit, but it may read too high with film capacitors.

[The Electrician]

How do you answer the objection I raised about the 15 uF MKT capacitor that your meter showed has an ESR of .001 ohms? I said:

"I very much doubt that the Epcos 15 uF MKT capacitor shown here could have an ESR as low as .001 ohms.

See the data for this capacitor here: https://en.tdk.eu/inf/20/20/db/fc_2009/B32520_529.pdf

On page 21 we see that the typical ESR for a 15 uF capacitor is about .01 ohms, not .001 ohms."