LCR tweezers 100 kHz.

[iet]

Tweezers with a measurement frequency of 100 kHz are produced. There are well-known brands that have been on the market for a long time, and there are recently appeared new models. The latest trend is to display the maximum number of parameters on the screen. There is also a tweezers with a signature analyzer function. These tweezers are distinguished by high basic accuracy, wider measurement ranges and many additional useful functions that greatly facilitate the work of those involved in electronics.
Perhaps there are users of these tweezers and they could tell some interesting things based on their operating experience.
https://www.lcrresearch.com/pro1plus
https://appatech.com/as/en/707
https://lcr-reader.com/lcr-reader-r3.html

[iet]

User Manual.
https://www.lcrresearch.com/_files/ugd/97c2bb_73362b7481694861a96b1bed0670c66b.pdf
https://appatech.com/resources/APPA_707_700020056_User_manual
https://lcr-reader.com/R3/Downloads/Documents/LCR-Reader_R3_manual.pdf

[Feuerbard]

[US$79.99 20% OFF]LCR-1S Smart Tweezers LCR Tester 100kHz CNC Metal Case High Accuracy Portable 1.47" Color Display Intelligent Auto-Range Function Measurement & Analysis Instruments from Tools on banggood
https://ban.ggood.vip/155NT

About $45 on taobao

[iet]

Specification LCR Pro1 Plus.

[Aldo22]

The specifications look very good, but the price is quite high for this type of device.
https://www.batronix.com/shop/lcr-meter/LCR-Research-Pro1-Plus.html

[iet]

The price is set by the manufacturer, based on the specification and functions of the device.
Most of the price is probably related to the frequency of 100 kHz or not?

[Aldo22]

The price is set by the manufacturer, based on the specification and functions of the device.
Most of the price is probably related to the frequency of 100 kHz or not?

As I said, the specs sound good, but would I want to buy it for that price?

You can buy a UNI-T UT622E plus a Zoyi MD-1 (for quick and dirty) and still pay 100 euros less.

But maybe it's worth it? I haven't compared all the specs.

[Sensorcat]

I have the LCR Pro1 Plus. Since I need it for work, I had a priority on performance and quality, not price.

Advantages:

• very good built quality
• bright display
• well-thought user interface
• very competent reply to email with highly specialized questions

The email contact was three or four times and customer support of Keysight, Tektronix, LeCroy, or R&S could learn a lot from LCR Resaerch...

There is much cheaper competition, but I would recommend it if the price is not a problem.

[iet]

As I said, the specs sound good, but would I want to buy it for that price?

LCR Pro1 and LCR Reader MPA are very close in price and occupy the segment of the most expensive smart tweezers. There is very little information on their real practical application, so everyone decides for themselves whether to buy expensive tweezers.

[iet]

You can buy a UNI-T UT622E plus a Zoyi MD-1 (for quick and dirty) and still pay 100 euros less.

You will also have to buy tweezers of this model for it.
https://www.ebay.com/p/1337077889?iid=186269591071

[iet]

There is much cheaper competition

I would like to see these devices in real work. In the pictures everything is very beautiful.

[Aldo22]

You can buy a UNI-T UT622E plus a Zoyi MD-1 (for quick and dirty) and still pay 100 euros less.

You will also have to buy tweezers of this model for it.
https://www.ebay.com/p/1337077889?iid=186269591071

Yes, that is correct. UT622E comes with “Four-terminal Kelvin test leads”.
There are also Uni-T branded tweezers, but they are probably the same product as the one you showed.
https://youtu.be/SZRRKZ4T6oA
Still cheaper.

You might ask Sensorcat if he would have bought the LCR Pro1 Plus if he had to pay for it with his own money. 
I mean, a Siglent SDS804X HD costs about the same (just for comparison).

But I'm sure it's great if you don't care about the price.

[iet]

I mean, a Siglent SDS804X HD costs about the same (just for comparison).

Depending on the type of work, we choose either a good oscilloscope or tweezers. And it is better to have both. As for the comparison of tweezers, it is better to compare them in real measurements and over the entire range.

[iet]

Drift in the open state in the third decimal place.
I have already taken measurements in another topic, in the picofarad range. I got a few more 1 pF capacitors. And here is the total capacity of 8 capacitors connected in series.

[Aldo22]

There is much cheaper competition

I would like to see these devices in real work. In the pictures everything is very beautiful.

What is actually your point?
Apparently you own these tweezers, so what's your question?
Is this just about advertising?

[iet]

What is actually your point?

The point is that I showed how the tweezers work in the picofarad range, that is, their capabilities and compliance with the specification.
My topic does not have advertising videos and pictures, like others.

[iet]

My topic is about tweezers with a maximum measurement frequency of 100 kHz. This is the main difference from other tweezers with a maximum measurement frequency of 10 kHz.
Why do you need a frequency of 100 kHz? Let's look at the specification. 100 kHz is used in the nH and pF range. In addition, this frequency is used to measure the ESR specified in the documentation for different types of capacitors.
I have already checked the picofarad range, now the nH range.
I solved the problem this way. I bought smd resistors with the designation 0. The inductance of such a resistor is 5 nH. I connected 6 resistors in parallel.

[Kean]

My topic is about tweezers with a maximum measurement frequency of 100 kHz. This is the main difference from other tweezers with a maximum measurement frequency of 10 kHz.
Why do you need a frequency of 100 kHz? Let's look at the specification. 100 kHz is used in the nH and pF range. In addition, this frequency is used to measure the ESR specified in the documentation for different types of capacitors.
I have already checked the picofarad range, now the nH range.
I solved the problem this way. I bought smd resistors with the designation 0. The inductance of such a resistor is 5 nH. I connected 6 resistors in parallel.

I've noticed in your various topics on LCR tweezers that you post many photos of measurements, but you rarely make any observations of the result.
Like Aldo22, I am not sure the point you are trying to make.

• It is not obvious if you have made any efforts to "fudge" the numbers.
• You don't explain if you had to do any special short/open calibration to get these readings.
• You don't compare the measurements to bare side-by-side pads/traces on a PCB - e.g. in your earlier sub pF measurement
• You don't compare the results against the device specification.

For example, in this reading with 6 parallel "5 nH" 0R resistors...
How does that result meet your expectation considering the tool has an accuracy spec of "2.5% + 5nH" in the 1000nH 100kHz inductor range?

[mawyatt]

My topic is about tweezers with a maximum measurement frequency of 100 kHz. This is the main difference from other tweezers with a maximum measurement frequency of 10 kHz.
Why do you need a frequency of 100 kHz? Let's look at the specification. 100 kHz is used in the nH and pF range. In addition, this frequency is used to measure the ESR specified in the documentation for different types of capacitors.
I have already checked the picofarad range, now the nH range.
I solved the problem this way. I bought smd resistors with the designation 0. The inductance of such a resistor is 5 nH. I connected 6 resistors in parallel.

Please note that placing 6 SMD Inductors in parallel like shown does not create an overall inductance that is 1/6 the single value inductance. The individual H Fields couple and the overall inductance is influenced by such and doesn't follow the lumped element 1/n parallel rule.

If you think of a wire inductance, the inductance is not inversely proportional to the wire diameter but more complex as Grover's Equation predicts. The change in inductance wrt the wire diameter (dL/dD) is much slower than expected by simple paralleling as 1/D would expect.

https://www.allaboutcircuits.com/tools/wire-self-inductance-calculator/

The same goes for a Flat wire, the overall inductance is not inversely proportional to the flat wire thickness as shown here:

http://www.finetune.co.jp/~lyuka/technote/inductor/inductor-straight-flat.html

For example, a 2512 Zero Ω Resistor should have 2.2~2.5nH self inductance, and a 1206 1.5~1.8nH based upon the above. Note these are highly dependent on many variables, some not accounted for in the listings but should give a rough estimate of the expected self inductance.

So from your example we don't think the individual self inductance of the SMD resistor shown is ~5nH, likely much less, and the parallel result is also in question.

BTW look at the impedance of the DUT at the expected frequency, for example 1nH is just ~0.63mΩ @ 100KHz, that's going to be very difficult to resolve considering the limited test current available from the tweezers. This is where a quality Bench Lab Grade LCR meter earns it's keep

Best

[Sensorcat]

In addition to the explanations of mawyatt in reply #18, it is important how the 6 resistors are geometrically arranged, as the inductance of the wiring contributes significantly to the overall inductance at these small values. Unfortunately, the image in reply #16 does not show this. We see only one element and have to guess where the other 5 are. With a few mm of wiring (or not) from element to element and instrument, everything is possible from less than the expected value of the lumped element model parallel connection, to much more. So we cannot draw any conclusion from what is shown there.

While I'm at writing: Aldo22, since it is my business, I did spend my money on the LCR Pro1 Plus. What changes if you buy for your business is the value of time. In business, 'time is money'. In hobby work, there is no monetary value in time. So business owners tend to invest more in tools, if they expect to save time in any way. This is a trivial, please don't think I want to lecture you, but there is something that I discovered only when I began to be in the situation of the business owner: The issue of time is already at work in procurement. That means, if buying the more expensive instrument is expected to save time by 'being done with buying' for a class of instrument and a couple of years, the business owner is often inclined to invest more, to get the job of buying finished. In that sense, I do not regret the decision for the LCR Pro1 Plus.

[mawyatt]

In addition to the explanations of mawyatt in reply #18, it is important how the 6 resistors are geometrically arranged, as the inductance of the wiring contributes significantly to the overall inductance at these small values. Unfortunately, the image in reply #16 does not show this. We see only one element and have to guess where the other 5 are. With a few mm of wiring (or not) from element to element and instrument, everything is possible from less than the expected value of the lumped element model parallel connection, to much more. So we cannot draw any conclusion from what is shown there.

We had "assumed" the SMD resistors were stacked one on top another per the image, and thus using the {wire cross-section} equivalent to show the relationship on inductance with paralleled devices or conductor "thickness". Of course this "assumption" could be totally wrong!!

Best

[iet]

Thanks to everyone for the comments.
I didn't even think that measuring the inductance of 6 resistors connected in parallel would cause such a violent reaction. Naturally, there is nothing extra there. The resistors are simply soldered together. I wanted to check the ability of the tweezers to measure inductance less than 1 nH, and not get an accurate result. If I had inductances of 0.1 nH, then we could talk about accuracy.
Therefore, I would like to ask the developers of LCR Pro1 and LCR Reader MPA how they check their parameters from the specification.

[iet]

Please note that placing 6 SMD Inductors in parallel like shown does not create an overall inductance that is 1/6 the single value inductance. The individual H Fields couple and the overall inductance is influenced by such and doesn't follow the lumped element 1/n parallel rule.

Axial inductors 1 uH - 10 pcs.
Average value - 880 nH. Connected 5 pcs. in parallel. Inductance 170 nH.
It seems to work in some ratio.
I removed 4 SMD inductors with an inductance of 300 nH from the board and soldered them in parallel. The situation is similar to the previous one.

[mawyatt]

Please note that placing 6 SMD Inductors in parallel like shown does not create an overall inductance that is 1/6 the single value inductance. The individual H Fields couple and the overall inductance is influenced by such and doesn't follow the lumped element 1/n parallel rule.

Axial inductors 1 uH - 10 pcs.
Average value - 880 nH. Connected 5 pcs. in parallel. Inductance 170 nH.
It seems to work in some ratio.
I removed 4 SMD inductors with an inductance of 300 nH from the board and soldered them in parallel. The situation is similar to the previous one.

Yes but not the 1/n as implied, probably more like 1/(n^x + k*n + b) or 1/(n^x) + k*n + b, where n is the number of paralleled inductors, x, k and b are constants/variables that depend on DUT Inductor test frequency, type, size, orientation, connection method, and proximity effects.

Point is it's not a simple 1/n as implied by paralleling equal valved resistors

Best

[iet]

• You don't explain if you had to do any special short/open calibration to get these readings.
• You don't compare the measurements to bare side-by-side pads/traces on a PCB - e.g. in your earlier sub pF measurement

I already wrote about this in another thread.
For correct measurement in the picofarad range, two things must be done.
Calibration with closed and open probes.
The distance between the capacitor leads must match the distance between the tweezers tips. If the distance does not match, the error will increase.
All this is well analyzed and entered into the table in the information from LCR Reader.
https://www.wnie.online/wp-content/uploads/2021/02/Siborg-Systems_Accurate-Measurements-of-Extremely-Small-Capacitance-Values-2.pdf