Page 1 of 1

6221 driver problem

Posted: April 8th, 2013, 2:49 pm
by scal_pas

I'm using the Labview 2009 drivers for the Keithley 6221 ("Keithley 622x LV 2009") and controlling it via GPIB. I'm having a couple of problems with the provided example VIs.

1) "setup dc current source example". The vi activates the 6221's output, but the current is always zero, regardless of the current level, range, and compliance settings.

2) When using the "Wave gen" I get an error in the labview programme (see below), which causes it to stop. This happened for a sine wave using the VI's default values. I then deactivated the "check for SCPI errors". The 6221 still showed the error on its front panel, but the programme executed and output a sine wave. However the amplitude was 1 mA, despite setting it at 10 mA in the labview programme.

So, can anyone help me with this ?
Error -1074000000 occurred at Keithley 622x.lvlib:Error"
"Possible reason(s):

Instrument reports:
-222,"Parameter data out of range"

Complete call chain:
Keithley 622x.lvlib:Error
Keithley 622x.lvlib:KE6221 -- Set Wave
Keithley 622x.lvlib:KE6221 -- Set Sine Wave
Keithley 622x.lvlib:KE6221 -- Wave Gen

Re: 6221 driver problem

Posted: April 8th, 2013, 3:51 pm
by scal_pas
Ok I've found the problem. The drivers are programmed to use "." as a decimal separator, and my computer uses ",", so the 6221 didn't understand the current values being sent.

Re: 6221 driver problem

Posted: October 29th, 2014, 12:44 pm
by miguelf

I'm having the same problem. But I'm pretty sure that my computer uses a '.' as decimal separator, and SCPI commands being sent to source contain '.' as well.

I've tried everything, even sending the exact SCPI commands that Labview is generating through Keithley Communicator command line. But can't find the problem.


Re: 6221 driver problem

Posted: October 29th, 2014, 1:44 pm
by miguelf
Another strange behavior I'm getting, happens in most the AC waveform setting, e.g. in the Labview "KE6221-- Set Sine Wave":

Everything works, except when I try to set the amplitude of the sine wave to some value <=500nA. In this case the value that is considered by the source is 1uA, and I can go below the range 2uA.

Any help is ver much welcome