Current vs time in Keithley 6487 : Not able to go < 1s interval

[Tushar-graphene]

The problem we are facing is the following:

For interval based measurements (ON/OFF), we are not able to go beyond 1 s of interval, because the delay offered by the loop in program (this is what we suspect) is ~ 1 s and so the measurements with interval < 1 s is not possible.

A student in our lab tried troubleshooting it by keeping the "zero check delay" outside the loop which worked to bring down the interval time from ~ 3 s to ~ 1 s.

Beyond this she too was helpless and we got stuck. As far as instrument resolution is concerned (in relation to GPIB) it is around 1~2 milli seconds.

The instrument we want to interface is Keithley 6487.

Please find the file in attachments.

Thanks.

[Dennis_Knutson]

You haven't attached anything. Could you attach a snippet add well as the actual VI? I'm posting from my phone and can't look at a VI.

[Tushar-graphene]

PFA

[GerdW]

Hi Tushar,

you call a "Keithley Read" VI in your loop: what's inside this VI?

Which measurement mode do you use? What does the manual say about measurement times for this mode?

You enabled "Zero check" and "Zero Correct" features: both features usually require some "processing" time for your Keithley device (as should be mentioned in the manual).

It doesn't make sense to enter a value of "0.0333" for "interval between measurements" when the timing function expects values in milliseconds!

Did you read the LabVIEW help for that function?