torque offset not offsetting

[Martell]

I am trying to set my PCI-7344 Motion control card to work with a uni-polar (0-10v) drive. The documentation all says that this is possible by offsetting the torqe either in MAX or by writing a VI, but is unclear about how to choose the settings. I have tried -5 to +10 with a 5v offfset and 0-10 with a 5v offset. It appears that either way the PID loop is pulling the control signal back to where it should be for bi-polar 10v.

Thoughts?

[Rodj]

What drive are you using? Can you point me to a link on the web so I can take a closer look.

Thanks,

Rodger S.

[Martell]

It's an Automation Direct GS2 Drive.

http://web5.automationdirect.com/adc/Shopping/Catalog/AC_Drives_-z-_Motors/GS2_(230_-z-_460_VAC_V-z-Hz_Control)/GS2-25P0

They were very helpful in telling me how to set up the drive.

Currently I am testing the following voltage by hooking the UMI to a simulator and metering the card output. The actual drive is not involved, yet.

Thanks

Beth

[Scott_R]

Beth,

The motion controller should be configurable for unipolar. I will attempt to reproduce the behavior that you are seeing. I will let you know the results of the testing on my end.

Regards,

Scott R.
Applications Engineer
National Instruments

[Rodj]

Beth,

How do you have the drive configured?

Here is the link to the PDF I was looking at:

http://web5.automationdirect.com/static/manuals/gs2m/gs2m.pdf

On pages 71-78 (PDF pages not manual pages) it talks about configuring the analog input.

Thanks,

Rodger S.

[Scott_R]

Beth,

When you tried to configure the drive for 0-10V, what settings did you change? Did you try setting the positive and negative torque limits and the offset in Measurement and Automation Explorer under "Axis Settings" on the "Miscellaneous" tab? Try setting those to 10, 0, and 5 respectively. I am using a bipolar motor and my behavior varied quite a bit when I changed those settings. Try using those and then try autotuning your motor in the "Servo Tune" option under "Calibration."

Try this and let me know if you have any additional questions.

Regards,
Scott R.
Applications Engineer
National Instruments