Trying to read current values from Keithley 6220 getting error -1073807339 Timeout expired before operation completed

[sk515]

Hi all,

Im relatively new at labview.  Ive tried to search on the forums about this error, but I still cant seem to fix it.  I have a Keithly 6514 Electrometer, and 6220 Current source.  Im sourcing current, and reading the voltages.

I also want to calculate the resistance, at first I wanted to just read the values the current source was giving me to calculate the resistance, but I get the timeout when i try to use the read vi the 6220 came with.

I have attached my block diagram.  Any help is appreciated!

Thanks!!

[Adam W]

Hi sk515,

Do you know where in the program the error is occurring?  Can you isolate it down to one vi or sub-vi?  Since National Instruments does not support or maintain those drivers, if the error is driver specific, you might want to contact Keithly. 

If that error is happening in a VISA operation, there are some KnowledgeBases that might be helpful here and here.

Also make sure the settings are all correct on your device and your program.

Hope this helps!

Adam W
Applications Engineering

[sk515]

Yes so the error is coming from the Keithley 622x Read buffer sub vi.

All the settings should be correct.  If i remove that sub vi, everything works fine. 

I know the timeout issue has to do with the instrument not being able to return a value before the program needs it correct?

[Adam W]

Have you tried opening and trying to run just that subvi?  This might help you isolate further where the error is returning. 

Also, have you tried increasing the timeout value or the suggestions in the second knowledgebase I posted?

Regards,

Adam W
Applications Engineering

[sk515]

ok, so I have tried to run that  read instrument data vi, I cant run it by itself so i just made a basic program that basically turns the current source on.  If i dont tell the read instrument data vi to read any bytes, no error occurs, but that doesnt help because I get no reading. If I even tell it to read 1 byte, the error occurs. this is all in a while loop. (the read instrument data, and plotting) everything else occurs outside of the loop. I have also but a wait(ms) in the while loop as well.

I haven tried the knowledge base suggestions, im running through GPIB, im not sure if thats the same thing as VISA?


do you think the read instrument data vi is just messed up?

[Adam W]

Is the "read instrument data" vi part of the driver?  If you open it, what subvis are in it and what is it doing?  I don't know if it is messed up, or if a setting is just off.

Can you run a basic GPIB example?  You can find an example in the NI Example Finder by going to Help > Find Examples and then Browse to Hardware Input and Output > GPIB.  There is a vi in that folder that does a basic GPIB write and read.

Regards,

Adam W
Applications Engineering

[sk515]

Hi, thanks I will play around with that, the vi that comes with the instrument looks pretty similar to that, I might just make my own if that will work better. thanks again.