Smart LCR tweezers LCR Pro1-Russian RLC tweezers HB-14

[73's de Edd]

There are radio amateurs for whom the measurement of small capacitors is of great interest. Most likely, this is a rather specific field of measurement that you rarely encounter.
OK, who cares.
Capacitor 1pF.
1.0247pF.
Very good.

View attachment 45332

How quantatative is that reading of that low of picofarad value of capacitance, when you are swamping it with picofarads of hand capacitance with the fingers handling the tweezers ?

 

[caps]

How quantatative is that reading of that low of picofarad value of capacitance, when you are swamping it with picofarads of hand capacitance with the fingers handling the tweezers ?

I did not quite understand your question. Please tell me more precisely what moment interests you.

 

[caps]

Measurements in the circuit.
0.1uF/50V.

 

[caps]

1uF 400v.
Very good.
LCR Pro1.
ESR-14.989Ohm.

ESR meter 100kHz.
15 Ohm.

 

[SHA_S]

How quantatative is that reading of that low of picofarad...

Tweezers after calibration have very small capacitances of probes, with HB-14 it is usually 0.001 pF or less. If I understand the question correctly.

 

[caps]

1uF 450v.
LCR Pro1.
17.059 Ohm.

ESR meter 100kHz.
17 Ohm.

 

[caps]

Another capacitor 1uF 450v.
Thus, we checked the linearity of the ESR meter scale to 20 Ohms.
All perfectly.

 

[caps]

when you are swamping it with picofarads of hand capacitance with the fingers handling the tweezers ?

If I understood correctly, you meant this.
0.0000pF

 

[caps]

I will give a good example, why else besides small capacitors, we need this ESR 100kHz meter.
Most homemade ESR meters have a maximum upper limit of 20-30 Ohms.
In this ESR meter, the maximum distinctive value is 300Ohm.
Capacitor 3,3uF /450v.
Capacitance is almost normal, but the ESR is very high.
After 20 Ohms, the scale is nonlinear.
ESR ~ 40 Ohm.

 

[caps]

73's de Edd
To measure the capacitance less than 1 pF, it was necessary to connect two capacitors 1 pF in series.
Very good.
0.5124pF.

 

[SHA_S]

Quite high losses in 1pF capacitors, who is to blame, tweezers or a capacitor?
Can I see the losses in the capacitor type "K71-7" at frequencies of 1 kHz and 10 kHz?

 

[SHA_S]

Judging by the lack of an answer to the question, LCR Pro1 was sent to the trash.

 

[caps]

Two Russian tweezers measure ceramic capacitors in-circuit.
The measurement results are complete nonsense.

 

[Harald Kapp]

No wonder. In-circuit measurements require shielding of the component to be measured from the effects of other components, wiring etc. This can be done but requires additional test points and drivers to isolate the component to be measured.
True measurements usually require that you remove the component from the circuit, at least wit one pin (of a 2 pin component).

 

[caps]

It is clearly seen that Russian tweezers have big problems with measuring ceramic capacitors.
This is not a problem of the influence of other components, it is a quality problem of in-circuit measurements of these tweezers.
There should not be any special restrictions in the measurement of these capacitors, and even more so for an impedance meter operating in automatic mode.

 

[Harald Kapp]

This is not a problem of the influence of other components,

I disagree.
What makes you so sure about this?
This article is about resistors but equally valid for other components, too.

 

[caps]

Watch this moment carefully in the video.
6.48-6.58.
Measured SMD resistor 0 Ohm. Its name is a resistor-jumper.
The measurement results differ three times. So, it is absolutely not clear which of the tweezers can be trusted.

 

[Harald Kapp]

I don't want to argue the accuracy of these tweezers. They probably are as bad as indicated.
Good or bad: my argument about measuring in-circuit still stands.

 

[caps]

I don't want to argue the accuracy of these tweezers. They probably are as bad as indicated.

They have approximately the same accuracy, much higher than the accuracy of this resistor.
I can say one thing. Three times the difference is a disaster.
One more software flaw in blue tweezers is clearly visible, this is the need for constant calibration.
The huge difference in the measurement results of both tweezers suggests that, despite the general software, they work differently.Two Russian tweezers cannot provide the reliability of in-circuit measurements.
Measurement of a new electrolytic capacitor 1000uF 16v. The measurement frequency is 100kHz.
ESR-0.3Ohm.
Complete nonsens.

 

[caps]

What makes you so sure about this?

https://patentimages.storage.googleapis.com/a6/e6/4d/03566a4d6af76b/US6356086.pdf