Motion Control and Motor Drives

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PXI-7344 not outputing the correct range of voltage

Have a pxi-7344 board running under RT.
When axis 1 is moved in closed loop mode with encoder feed back(Absolute move) in the positive direction an output of +4 Volts is on the DAC.
When it is moved in the opposite direction -4 Volts is on the DAC.
For Axis 2 with the same setup and same commands the positive direction outputs 9 volts while the negative outputs 0 volts.
I'm still getting the full 10 volt range from both joints.
Reformatted the PXI HDD and re-setup all the axis, cards, etc.  Copied the same startup.exe file to *\ni-rt\startup\ and now Axis 2 outputs the +/- 4 Volts.
Are there any thoughts on what could have caused this to happen?  RT VI's I should run when initializing the joints to reset the system?
It seems like a really wierd error.  Not sure how I can fix it without reformatting the Hard drive.
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It sounds like the torque limit settings for that axis were somehow modified.  In Measurement and Automation Explorer (MAX), look at Control Loop Settings for your axes.  Select the Torque Settings tab at the bottom of the window.  This page has the torque limits which, by default, are defined in terms of a voltage range.  These values may have been altered at some point, causing your axes to have different ranges.
In the future, you could try using the Load Torque Limit.flx function to specify the primary and secondary output limits for that axis. 
Let me know if you have any additional questions on this issue.
Scott R.
Applications Engineer
National Instruments
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