USB 6218 BNC Self-Calibration and AO Voltage Problem- Please Help!

[jcannon]

Hi all,

I have a problem, hopefully someone can shed som light in this for me...

I am using a USB 6218 BNC DAQ device to parrellel AI and AO tasks... All has been working well with my vi until recently when the AO voltages have moved to a value of about 3V at rest (i.e. when the AO code is being not being executed)... When I power up my notebook and the device initialises without Labview open) the 3V AO is present... I then went to MAX to manually view/control the AO.... The lowest value AO does not drop below this 3V level even when set to values <3... But it will output correct values when the input I select is >3V.

,

To solve this I have tried to do a Self-Calibration, which gives the the following error code: 201295.

After searching for error code solutions I reset the data configuration in MAX (i.e. Tools>Rest Data Configuration), but this not worked..

Any suggestions would be greatly apreciated.

Thanks for your time.

Regards,

Jack

[jcannon]

Sorry....

I am using Windows XP (SP3) and updated the driver after the problem started to NI DAQmx 9.6 Driver (to no avail).

Thanks...

[Mockingbird]

Hi,

Are you doing this self-calibration in MAX? or are you using LabVIEW to do the self-calibration? Also, is there anythinig plugged into the AO slots while you're doing the self-calibration? This generally causes an issue with the calibration so that might be what's going on.

Let me know if that works!

[jcannon]

Hi Gabriel, Thanks for the reply... I noticed the problem when the external instrument I was control was no longer responsive... I went into MAX to troubleshoot and did the self-cal etc... I had disconnected all AI and AO leads for the self-cal as I normally would... The +3V AO occurs immediately from the the device is connected to the notebook at start-up... No code needs to be executed... All very strange... I am thinking it might be a hardward problem...? Is there anything you could suggest before go the trouble/expense/project delay assocuated with sending it to NI for servicing? Thanks, Jack

[jcannon]

I should also add that the specific error message to accompany the code say the signal used for calibration is changing during the self-cal process (despite no AI or AO connections).

[Mockingbird]

So the self-cal doesn't work right? And you are doing this without any other pins connected aside from it being connected to your notebook? This is only showing up on one channel right? It looks like this might be a hardware issue especially if the self-cal doesn't get rid of the 3 V that you are seeing on the AO so the best thing to do might be to call in to NI support and take this up with them.

[jcannon]

Ok... Thanks....

[Mockingbird]

Yup, if you call in to NI they will be able to ascertain if it really is a hardware issue that's occuring. From what you've told me so far it does sound very likely that you would need to repair this.