Changing default directions

[Perryg114]

I set up a simple stepper motor from automation direct in Labview 2009 and when I moved it to another machine with the current verson of labview, the direction was reversed. So now when it is homing it is moving forward away from the limit switch. Yeah I could cross some wires and get it to work but it would be a troubleshooting nightmare down the road. The limit switches are correct. The reverse switch activates with pressed. So why is the motor going backwards. There are only two wires to deal with and if they were reversed it would not change directions at all. It will change directions so it is getting a rotation signal. I have not been able to find a simple check box in MAX to change this. I would think this would be a handy feature to have. I am using a PCI-7344 motion controller and a UMI breakout box on both setups. I don't see why Labview versions would invert the rotation direction (just for fun) but similar things have happened. I am sending the motor controller step and direction signals only and the limit switches are wired to the UMI box.

Perry

[Perryg114]

I have done a considerable amount of reading of manuals and both the manual from the PCI-7344 and the breakout boc say you can change the default state of the direction output. However, nowhere does it say how or where to make these changes. It says software programable. Well I have seen no way to change this in MAX or Labview eventhough there is a vi that says it can change this there is no input for it. There is an input to change the initial state of the step output but none that I can see that change the state of the direction input which is what you want to change. For some reason the new version of MAX/Labview has changed the default state which is causing the reversed motor operation. This is a bug in my opinion.

Perry

[Cole_R]

Hi Perry,

Is the motor you are working with configured for Step and Direction mode or Clockwise/Counterclockwise?  You can change the Stepper Polarity in Measurement and Automation Explorer under 'Axis Configuration' and then choosing the Stepper Settings tab.  This settings determines whether a high direction output is forward or reverse.