Smart SMD tester MS8911.

[MiniCheck]

I made a more advanced device for zeroing. At the same time, it can be used as a stand for tweezers.

Is that something you have to do before using them?

[iet]

Is that something you have to do before using them?

Short Circuit Zeroing: First, select the test frequency that you want to zero. Insert a short-circuit piece into the test socket,
whether using SMD test tweezers or clamps. Short-press to enter zeroing mode. The instrument will automatically
measure and execute the corresponding short circuit zeroing after identification.
This is written in the manual. You decide for yourself whether to do zeroing or not. For example, you shorted the probes 1-3 times and you have N milliohms on the display. You decide whether this error will affect the measurement results or not. If not, then there is no need to zero. If you measure low-resistance resistances and picofarads, then you must zero. In addition, I have the corresponding components soldered onto the test boards and I immediately check the zeroing result.

[iet]

To finally solve the problem of the tips, I made another pair from copper plates 1 mm thick. Everything works fine.

[iet]

Measured 8 resistors connected in series, 10 MOhm. There is nothing to check the result with. MS8911 and a multimeter - 60 MOhm.

[iet]

After carrying out all the necessary things in the milliohms range, I measured the resistance of two 1 mOhms resistors connected in parallel.

[indman]

After carrying out all the necessary things in the milliohms range, I measured the resistance of two 1 mOhms resistors connected in parallel.

[4thDoctorWhoFan]

After carrying out all the necessary things in the milliohms range, I measured the resistance of two 1 mOhms resistors connected in parallel.

Perhaps I am missing something but why do you keep posting about the Fnirsi LCR-ST1 when this thread is titled about the MS8911?
I mean, there is a dedicated Fnirst LCR-ST1 thread.

[mawyatt]

Also, how much current do these tweezers utilize thru the DUT for low Z measurements?

Best,

[iet]

Also, how much current do these tweezers utilize thru the DUT for low Z measurements?

Best,

A very interesting thing. And the most interesting thing is that this information is not available for any tweezers.
https://upload.sunsky-online.com/res/guide/TBD06051996Manual.pdf
https://mastech-group.com/resources/QSG+%E8%AA%AA%E6%98%8E%E6%9B%B8/GLO_%E8%AA%AA%E6%98%8E%E6%9B%B8/GLO%E8%AA%AA%E6%98%8E%E6%9B%B8_%20%20MS8911.pdf
https://www.lcrresearch.com/_files/ugd/97c2bb_73362b7481694861a96b1bed0670c66b.pdf

[mawyatt]

This can be measured relatively easy with a small DUT resistor, say 1 Ω. Attach a DSO across the DUT and observe the measurement waveform from the tweezer, or if a DSO isn't available use a DMM. Keep the frequency low for the DMM since they usually don't respond well at higher frequencies.

Another option if one has a DSO with 50 Ω input impedance, is use the DSO 50 Ω input Z as the DUT and simply measure such with tweezers.

Maybe some folks with these tweezers can perform this simple test and report th results, we would IF we had any tweezers, unfortunately we don't!!

Best,

[iet]

This can be measured relatively easy with a small DUT resistor, say 1 Ω.

There are different ways to check.
I got the result that interested me. To do this, I had to put my hands on it and work a little. These capabilities are embedded in these tweezers, you just have to try to implement them. Such measurements are not an end in themselves, but a way to check real parameters.
A lot of talk about the diode function.
Actually, we must not forget that the tweezers are a bridge LCR meter. The D function is additional. But it is not made like in multimeters. That is, it is not finished. FNIRSI should either finish it or remove it altogether. And instead of a diode, make a measurement of the DCR resistance. This is done in the MS8911.
And if possible, then do it like in the LCR Pro1 Plus.
In a short period of time, an analysis of the serviceability of the semiconductor junctions of the diodes and transistors is carried out for breakage, partial or complete breakdown.
After the analysis, we see the result on the display.

[iet]

In this case, ST1 indicates low resistance, which corresponds to the short state.
For the correct interpretation of the short state, it is desirable that the tweezers could indicate 10 mOhms, or even better 1 mOhms. Then it will fully display the real situation.
Here is good information.
https://www.fluke.com/en/learn/blog/digital-multimeters/how-to-test-diodes#:~:text=A%20bad%20(opened)%20diode%20does,0.4%20V)%20in%20both%20directions.

[iet]

Faulty transistor.

[iet]

In-circuit measurement of diodes.

[iet]

There was such an opportunity and I bought a used Atlas DCA55. I checked the diodes on the board again, which were checked with two tweezers.