ESR meter in the battery tester

[caps]

Hi everybody.
I constructed my ESR meter according to the known scheme of Manfred.
http://ludens.cl/Electron/esr/esr.html
The board was inserted into the battery tester.
The scale is 0.005-10 ohm.

 

[(*steve*)]

Yes, that seems to be what you did.

 

[caps]

I am glad that it is clearly visible.
By selecting the measurement modes of this circuit, it was possible to achieve an almost sinusoidal signal.

 

[caps]

Specifications.
ЕSR-0,005-10Оhm
F-100kHz
Vpp-100mV
Measuring probes-50cm.
On the meter there are gold-plated contacts for connecting capacitors.
There is no potentiometer for zero adjustment, because there is no drift with stable power supply.

 

[caps]

The battery tester was chosen specifically to not use the eps tables.
Green sector.0,005-0,5 Ohm corresponds to the range of capacitors 10000uF-100uF.
The small sector.0.5-2 Ohm corresponds to the range of capacitors 100uF-10uF. Capacitors of small capacity fall into the red sector.
The scale was calibrated with precision, non-inductive resistors.

 

[(*steve*)]

Ok it seems you don't have a question. Perhaps you should have posted this in another section

However, I would advise you to double the frequency from 50kHz to 100kHz. ESR is typically specified at this frequency.

 

[caps]

I already wrote that my ESR meter works at a frequency of 100 kHz.
You can transfer my topic to another place, there are no problems.

 

[(*steve*)]

I already wrote that my ESR meter works at a frequency of 100 kHz

Fine, the original circuit you referred to use 50kHz.

Presumably your meter has fixed leads and hence the zero can be set one and forgotten. I usually use a set of dedicated probes for mine, but sometimes I change to another set (mine can use regular multimeter probes) and hence the lead resistance can change.

Whilst reading your thread, and also designing a circuit which needs Kelvin connections to a sense resistor and possibly polymer caps I have been wondering why ESR meters can't use Kelvin connections to the capacitor. If I needed to measure ESR in the region of a couple of millions it would make sense to have that sort of measurement.

 

[caps]

This meter was not designed for very accurate measurements of ESR. It is made for rapid express analysis of capacitors. Good-bad. Calibration was performed only for the limits of sectors,although it is possible to mark the scale more accurately.
My circuit is slightly different from the original and was made at a frequency of 100kHz.

 

[(*steve*)]

Perhaps you can post the circuit for the benefit of others.

One thing I didn't comment on earlier is the somewhat imperfect triangular waveform in post #3 in this thread that you describe as a sine wave.

 

[caps]

One thing I didn't comment on earlier is the somewhat imperfect triangular waveform in post #3 in this thread that you describe as a sine wave.

Does this somehow affect the measurement of the ESR capacitors?

 

[(*steve*)]

It does have a significant harmonic content so your measurement may be affected a little by it.

Having said that, I don't know if ESR meters typically use a more pure sine wave.

 

[caps]

Different meters have different signals.

 

[caps]

Tantalum capacitor, 220μF in the circuit.