Hearing relay and voltage drop between measurements

Hi,

I am using KXCI to control a K4200 device and doing a very basic measure, apply voltage, measure current.
I am running with python the example in the manual Program 2: Basic source-measure (user mode) slightly modified to do a voltage sweep, and using a 80kohm resistor as DUT.
Below the pseudo-code:

US
IT1
BC
DR1
DV1, 4, 0, 1e-2
DV2

for V in range(0, 0.1, 0.01):
    DV1, 4, V, 1e-2
    I = TI1
    print(V, I)

The program is running, and doing the measurement, but I can hear at every points some relay "clicking" inside the K4200,
and If I use an external voltmeter on the resistor, I can see a short drop of voltage at every point.

How to avoid those voltage drops ?

The sweep program above is just to provide an example, because we have to investiguate "by hand" very sensitive samples,
and such voltage drops can destroy them.

best regards

Does your SMU1 also have a 4200-PA?

In your pseudocode, you have a DV2 but no other parameters.  Is SMU2 playing a role in this setup?

If you run an ITM out of KITE for the voltage sweep on the 80KΩ, any clicking then?

Sounds like some range selection issues are going on with the clicking.
Especially if you have the 4200-PA, you could try using the RG command to exclude some of the lowest and most sensitive ranges.
Without a pre-amp, the 100nA and higher ranges are available from the SMU.

​​​​​​​

SMU1 and SMU2 have both 4200-PA.
SMU2 is not playing any role right now, I am using DV2 without parameter to disable him.

I don't know what is KITE, but if I run an ITM in Clarius, the "resistor sweep" one, I can hear clicking before and after the sweep, but not at every point.

With now a resistor of about 100kΩ, I measure between 0 and 10mV and the measured current is below 1e-7A.
I added the RG command and if I am using a range above 1e-5 A, the clicking disappeared, but below 1e-5 A they are back.

The range selection issue gave me the idea to play also with the compliance value :   DV1, 4, 0, 1e-2.
1e-2A was too high and setting the compliance to a reasonable value a bit above the expected measure range removed the clicking !