How to write a program for solar cell simulation with keithley 2420

[jyot445]

Hi,

I  am new to this program I am trying to write a program for taking various I-V measurement of solar cell by making Keithey sourcemeter as a source and measuring device too. As I used the subvis in the driver software . The program is not getting executed. On keithley  screen it's showing as "OUTPUT can't be displayed when auto ohms on" and it shows specifically while measuring voltage.can you people please help me out of this?

[Bob_Schor]

Do you know LabVIEW?  Have you taken a class, done assignments, know how to write (simple) LabVIEW Code?  Do you know how to interface with devices, whether through a Serial Port or through DAQmx?

If the answer to these questions is "No" (or partly No), avail yourself of the Tutorials on LabVIEW (see first page of this Forum for some links, you can also browse the Web for "LabVIEW Tutorials").  Spend some time learning how to connect to your device.  Learn about MAX, the Measurement and Automation Explorer, which lets you "test" connecting to your device with LabVIEW and exploring its capabilities, including how to set it up to give you data.

Bob Schor

[GerdW]

Hi iyot,

it will also help to read the manual of your Keithley device: this way you learn which commands to use...

[cstorey · Accepted solution]

Post what you have and we can fix your code.  Without code, there's not much help anyone can provide.

From that error you have not configured the measurement properly, or early enough..it defaults to resistance and until you change it to voltage you cannot specify any other measurement settings like range or compliance without errors.

[jyot445]

thanks a lot, I was able to do it correctly as I inserted a visa write with the command: READ?  and then using the palettes of 24xxx.I am glad that you didn't do the comments like the previous ones to discourage me as i did all the basic youtube tutorials then started the program

[cstorey]

If you require further help, post your code, and you will get great help here.  

[proland1121 · Accepted solution]

There are also many example programs within the forums for conducting solar cell measurements using the Keithley 24xx series SMUs.  look around a bit for a variety of examples.

here are a few tips for your measurement

1) use "remote sense"; 4-wire configuration (described in depth in keithley manual). this compensates for the resistance of your test leads

2) use the Keithley's built-in sweep function (as opposed to a for loop of "set voltage", "measure current")

    2a) this requires setting up the memory buffer and would be optimized by evaluating the keithley's registry for the completion of the sweep (reference the 24xx manual)

3) Your solar cell will have a small settling time after each voltage change.  make sure you use the source/measure delay parameters (5-20 milliseconds should suffice for most single junction semiconductor devices.  Organic/perovskite solar cells will require a longer delay).  An easy way to determine if your delay is sufficient, is to perform two sweeps (neg to pos and then pos to neg).  If the two curves show hysteresis, consider increasing the delay.