Andrea C

When using the scan related commands, only one channel relay will be closed at a time.
If two or more channels are closed, the measured value will the combined ohms.

If the multiple closed channels is really what you need, you can close channels and separately command the dmm to measure.  You will need to also manage the backplane relays to connect the dmm to the switch hi and lo.

Are there any differences in the length of cables for your 20-channel setup vs. this one with only 5 channels?

If longer delay is allowing a good outcome, it implies a difference in the time constant of your DUT.

Does it stop reporting the overflow if you turn off the open lead detection?  The reported overflow could come a saturated measure range or from a detected open lead.  Since more delay fixes the overflow, this implies it is coming from the measurement from after the open lead detection has occurred.

To look into it, you might put a scope on the Card Sense HI and LO terminals.  When doing 4-wire ohms, the current is forced on the HI and LO and the resulting I*R is measured on the Sense HI and LO.
Is that spiking and requiring more settling time vs hte 20-channels setup?
 

For control of 3706A from .NET (C#), I'd suggest:

approach 1:  use a VISA layer and directly send the instrument commands (3706A Reference Manual)
approach 2:  use IVI driver.  This will leverage NI VISA runtime to communicate with the 3706A;  driver commands are translated to the instrument commands for you.

Both NI VISA and the IVI driver distribute some sample code in C#.

 

The Test Script Builder (TSB) software is giving a means to interact with the computer inside the instrument via the command API and scripting engine.  The only "file system" that has is the USB thumb drive on the instrument.

To have the data available in PC for saving to a CSV on the HDD:
try the internal web page of the instrument.  There is an applet for Extract Data (download buffers to CSV on PC).
Or move to Python or similar and read back the result of printbuffer() or print() commands.

Interesting.  I think it is related to the starting up into CC mode.
Datasheet does not tell us, but the output capacitance on the power supply is significant.
Slower V/sec slew rate will mean less displacement current.
How are you measuring the current in this setup?  Hi side or lo side of the 45Ω resistor?

If your concern is too much current when started up this way, some series R and use of the remote sense lines from rear panel could help.  Just mind the max 1V delta V between force and sense.

 

Need you to clarify on connections.  Where is the HI and the LO?

Your experiment sounds a little bit like Ion Beam Measurements.
Check out section 4.3.5 in our handbook:
Keithley Low Level Measurements Handbook

You may need to create a bias condition to attract the charge to flow through the amp measure function of the electrometer.

Your reference to KITE tells us you have the older 4200-SCS running on Win7 or earlier.
Evidently some file corruption has occurred.
You could try a reinstall of the KITE environment.

More drastic would be to catch the Acronis restore during boot up.  Most of the older 4200 will have an as-shipped image in the Acronis software.   Check the manuals on use.

Are you recently using the tool in a new way and encountering this error?

 

Thanks for the videos.
It behaves like the touch panel is receiving touch to change measure function.
Something is wrong in your display.

What happens if you place the instrument on different screen?  Swipe to graph or stats screen?  Does it stay there?

 

Seems you are saying that the DCI measure function returns overflow for the 3A and lower ranges.
Both front and rear.  No connections and still get overflow.
However, the 10A range available on rear only, is somewhat functional.

To me, it sounds like a malfunctioning meter.
Firmware unlikely to help such a symptom.

Separate from DCI is the digitize current measure function.  Does that still work for the 3A and lower ranges?

If you are seeing the OCOMP indicator when you turn the voltage source on, this means the maximum current (current limit) has been encountered.
If this occurs even for open circuit, I suspect some malfunction in the instrument, or your cabling is not what you think it is.

From front panel, you can adjust the amount of current limit.

Both the reference and user manuals detail the procedure.
 

From Reference Manual: